Don't jump too far ahead -- medicine is a secondary issue right now. The important thing is to go see someone who is trained in mental health issues and get a diagnosis. When someone is in a depressed state they don't realize how messed up their thinking is -- people end up thinking they must have done something wrong to get in the state they are in. It's very hard to be objective in this situation and almost impossible to self-diagnose.

Any thinking about suicide, even without specific intent, is a symptom of depression.