I agree with Brunnen-G. The hyper one minute depressed the next is the deffinition of manic-dression, but also can applie to teen angst.

I myself had nights were I stayed up late worring about my faults. I also had/have a short temper at times, and can become easily disguraged with difficult tasks. Flying into a rage over difficult homework assignments was some what common. I have setteled down, I think it was just difficulties dealing with puberty.

I'm not saying your problem is the same. It sounds like you may have actuall manic depression. I could ussualy relate my anger, frustaration, and morose moods to actuall problems (grades, money, girls, the ussual for a teenager). If you can't find a reason for these bouts of depression then you deffinetly need to seek help from a real person, parents, friends, siblings, priest, doctor, etc. There is only so much aid we can give you via the internet. Especially with suicideal depression, even if you thought you had reasons to kill yourself I can assure you you didn't. There is no reason to take your own life.