Clinically reviewed by Dr Muhammad Najam-Ul-Arfeen, General Practitioner
Bachelor of Medicine and Bachelor of Surgery (MBBS)
AHPRA-registered
Last updated: 21 September 2026
You’ve been feeling off for a while, not quite yourself, and it’s hard to tell whether this is depression or just a rough patch. Many people find themselves asking exactly that.
This guide describes depression symptoms in four groups (emotional, cognitive, behavioural and physical) so you can compare them with your own experience. It can’t diagnose you. It can help you decide whether to talk to a GP.
What Is Depression?
Depression is a mental health condition that affects mood, thinking, and daily functioning persistently, not just for a day or two. It goes beyond ordinary sadness: it shapes how you feel, how you think about yourself and the world, and how well you manage everyday life, often over weeks, not hours. For many people, it feels less like sadness and more like heaviness, numbness, or losing interest in things that used to matter. If these symptoms are affecting your daily life, you can learn more about depression treatment and support from a GP.
Is Depression a Mental Illness?
Depression is a mental health condition that affects mood, thinking, and daily functioning persistently, not just for a day or two. It goes beyond ordinary sadness: it shapes how you feel, how you think about yourself and the world, and how well you’re able to manage everyday life, often across weeks, not hours.
What Are the Symptoms of Depression?
Symptoms of depression, or the signs of depression, fall into four broad groups: emotional, cognitive, behavioural and physical. These are the signs of depression you might notice in yourself or someone else. Most people don’t experience every symptom below, and that’s normal; depression looks a little different in almost everyone.
Symptoms can also vary by life stage and circumstances. For a more specific look at how depression may present around menstruation, pregnancy, postpartum changes and perimenopause, see our guide to depression symptoms in women.
Having one or two of these doesn’t mean you have depression. What matters more than matching every item on a list is whether a cluster of these has been consistently present and is affecting your life.
Emotional Symptoms
- Persistent low mood or sadness, most of the day, most days
- A sense of hopelessness about things improving
- Feelings of worthlessness or excessive guilt
- Loss of interest or pleasure in things you’d normally enjoy (known clinically as anhedonia)
- Feeling emotionally flat or numb, rather than simply “sad”
- Increased irritability, sometimes more noticeable than sadness itself
Cognitive Symptoms
- Difficulty concentrating or making decisions, even small ones
- Persistent negative thinking about yourself, your situation, or the future
- Trouble remembering things or staying focused on a task
- Mental fog that makes ordinary thinking feel harder than it should
- In some cases, thoughts of self-harm or not wanting to be here anymore
If thoughts of self-harm are part of what you’re experiencing, please reach out for support now. Lifeline (13 11 14) is available 24/7, and you don’t need to wait for an appointment to talk to someone.
Behavioural Symptoms
- Withdrawing from friends, family, or activities you used to take part in
- Moving or speaking more slowly than usual, or conversely, feeling restless and unable to settle
- Finding it harder to get things done at work, study or home, or letting everyday routines slip
Physical Symptoms
Depression can also show up physically, in ways many people don’t immediately connect to their mood:
- Noticeable changes in sleep, sleeping much more or much less than usual
- Changes in appetite or eating patterns
- Persistent fatigue or low energy, even after rest
- Unexplained aches or digestive changes
Because this side of depression deserves its own proper explanation rather than a quick mention, we’ve covered it in detail in Physical Symptoms of Depression You Might Not Expect.
How Is Depression Different From Normal Sadness?
Sadness is a normal, temporary response to a difficult event, a loss, a setback, a hard week, and it tends to ease as circumstances change or time passes. Depression is different in both scope and duration:
| Feature | Normal Sadness | Depression |
|---|---|---|
| Trigger | Usually tied to a specific event | May have no clear single cause |
| Duration | Days, generally improves with time | Most of the day, nearly every day, for two weeks or more |
| Scope | Affects mood; other areas of life largely unaffected | Affects mood, thinking, energy, sleep, and daily functioning together |
| Response to positive events | Still able to feel genuine moments of joy | Difficulty feeling pleasure even in good moments (anhedonia) |
If low mood is affecting how you function, not just how you feel in the moment, that’s a meaningful difference worth paying attention to.
How Do I Know If I Have Depression?
Only a GP or other health professional can diagnose depression, and there’s no single symptom that confirms it, so it isn’t something to work out from a list. That said, a few honest questions can help you get clarity on whether it’s worth having a proper conversation with a GP:
- Has your mood been persistently low, most days, for two weeks or more?
- Have you lost interest in things you’d normally enjoy?
- Is this affecting your work, relationships, or ability to manage daily tasks?
- Have people close to you mentioned noticing a change in you?
If you’re answering yes to several of these, that’s a real signal, not proof of a diagnosis, but a good enough reason to talk to someone properly rather than keep wondering alone.
How Many Symptoms of Depression Are There?
There are nine symptom criteria used to diagnose major depressive disorder, the formal diagnosis for clinical depression. A diagnosis generally requires at least five of the nine to be present nearly every day for two weeks, with at least one being either low mood or loss of interest. These criteria are a framework clinicians use alongside the bigger picture of how you’re functioning and what else might be contributing, so they’re not a checklist to score yourself against.
You may also have come across the figure “17 symptoms of depression.” That number usually comes from counting either/or variations, such as insomnia or sleeping too much, or weight loss or weight gain, as separate symptoms. It isn’t a longer list, just the same criteria counted differently, which is why the number you see quoted can vary.
When Is Depression Considered Severe?
Severity depends on how many symptoms are present, how intensely, and how much they’re affecting your ability to function, not just whether you have depression at all.
Mild, moderate, and severe depression are genuinely different clinical pictures, and knowing where you sit matters for what kind of support makes sense. We’ve covered this in full, including the warning signs that need urgent attention, in our dedicated guide on severe depression symptoms and when to get help.
What About Grief, or Anxiety Alongside Depression?
Grief can look a lot like depression: low mood, withdrawal, disrupted sleep, and that overlap is normal after a significant loss.
The main difference is that grief tends to come in waves, with moments of genuine connection or even lightness in between, while depression tends to be more constant and pervasive. It’s also entirely possible to be grieving and depressed at the same time; one doesn’t rule out the other.
Anxiety and depression frequently occur together too. It’s common to feel both persistently low and persistently on edge, and if that’s your experience, it’s worth mentioning both when you speak to a GP, since treatment often needs to address both at once rather than just one.
Frequently Asked Questions (FAQs)
Can you have depression without feeling sad?
Yes. Some people experience depression mainly as numbness, irritability, or a loss of interest in things, rather than overt sadness. This is one reason depression can go unrecognised for a while; it doesn’t always look the way people expect.
Can depression come and go, or is it always constant?
It varies. Some people experience a single sustained episode; others have recurring episodes with periods of feeling well in between. Either pattern is still depression, not a lesser or more serious version of it.
Is it possible to have depression and still function normally at work or school?
Yes, often described as “high-functioning” depression. Someone can meet responsibilities outwardly while privately experiencing most of the core symptoms, which is part of why depression is sometimes missed by people around them.
How long do depression symptoms need to last before it's considered depression, rather than just a bad week?
Clinically, symptoms need to be present most of the day, nearly every day, for at least two weeks. A bad few days, even an intense one, doesn’t meet that threshold on its own.
Do I need to have thoughts of self-harm for it to "count" as depression?
No. Not everyone with depression experiences thoughts of self-harm. It’s one possible symptom among many, not a requirement for a depression diagnosis.
What comes before depression?
There’s no single thing that reliably comes before depression, but two patterns are worth knowing. Risk factors- a family history of depression, major life stress, chronic illness, or hormonal changes — can make it more likely. Separately, some people notice early signs in the weeks before symptoms fully take hold, like subtle changes in sleep, energy, irritability or motivation. You may see this described as “stages of depression” online; that’s an informal framework, not a recognised clinical model, and depression doesn’t follow a fixed progression. Noticing one or two early signs on their own doesn’t mean depression is coming, but if a few persist together, it’s worth mentioning to a GP.
Conclusion
If what you’ve read here feels familiar, the next step doesn’t need to be complicated. A GP can talk through what you’re experiencing, properly, without judgement, and help you understand what kind of support actually fits your situation, whether that’s therapy, medication, lifestyle changes, or a combination.
You don’t need to be certain it’s depression before you have that conversation; that’s exactly what the appointment is for.
HelloGP makes that first conversation easier to have. Our Australian-registered GPs offer confidential telehealth consultations, so you can talk through what you’re experiencing from home, on your schedule, without a waiting room in between you and the appointment.
If you need further support, your GP can discuss treatment options, prescribe medication where appropriate, and refer you to a psychologist or psychiatrist, including preparing a Mental Health Treatment Plan for Medicare-rebated psychology sessions.
HelloGP - Disclaimer
This article is for general information only and does not replace professional medical advice. Telehealth is not suitable for emergencies. If you have an emergency or are at immediate risk, call 000 or visit your nearest emergency department.