Do I have a condition .. ?

Okay so at random times I'll want to die. It can last afew days, hours, weeks, a week, or whatever., but I'll just go through random stages of wanting to die. And I cant help it. I'll feel really bad about my self feeling like theres nothing good and I just wanna die. It'll go away , and it comes at random times, but I want to know if this is a condition and if so what? Because I'll randomly get unhappy, feel like dying, feeling so bad about myself even when nothing bad is happening in my life.. is this a condition? If so tell me what, and it'd be nice if I could have a link[website] to about the condition if it is one. thanks. xxxx