How do I know if I'm sad or depressed?

Sadness and depression are often cofused, but they are not unrelated. A depressed person will feel sad most of the time, while a sad person doesn't necessarily have depression. The difference can easily be told if you consider how long you've been feeling this way, and is there a clear reason for it. Depression often lasts for weeks, months, even years and it might not even feel like sadness anymore, just general antipathy, emotional numbness, disinterest in everything. If you can tell the reason easily, for example, "I'm sad because my friend back-stabbed me", then it's most likely just sadness and it's easier to get better. Depression most of the time has multiple reasons that might not be easily identified, sometimes it just seems that you're sad for no reason. However, the single reason sadness in time might turn into depression, gathering up stones along the way and piling them on the heart. So, if you are cofused whether you are depressed or just sad, it might help you out to try identifying the cause of your feelings, how long you have been suffering and also, considering what would have to change.

IF the symptoms last longer, thinking about suicide, self harm, numbness, and slowly loosing all hope. These made me understand that I was depressed

Depression is a mental illness that can cause serious problems and affect your daily life greatly. Sadness comes around every so often and does not have the long lasting effects depression does. Depression can cause insomnia, changes in eating patterns, not going out with people as often or at all.

You need to spit it out and talk to an adult immediately. If you feel it's getting worse everyday, then I suggest you to get an appointment with a specialist. You cannot diagnose yourself.

If you are feeling empty and nothing is worth living for, that' how you know if you are depressed and not just sad.

because some signs and symptoms of depression include feeling sad, down or miserable most of the time or losing interest or pleasure in usual activities

Because the depression lasts for quite a long time and it affects you physically, emotionally, mentally and spiritually whereas sadness affects you but not for that length of time.

Depression continues over a long periods of time, while sadness comes ang goes and usually doesn't last that long.

It's not just a little hard for you to get up in the mornings. It's the most difficult thing in the world to force yourself to get up, to force yourself to do what you need to do. You just want to lay down and sleep rather than live your day. Things that once made you happy do not seem to have any affect and you go into these down moments where you honestly wouldn't care what happened to do. It's very hard to confuse sad and depressed if you're both.

Because you literally can't face the world and your mood is changing all the time. One minute your ok the next minute you are shouting at someone or getting irritated. You just want to sleep and be by yourself and sleep.