help with possible mental illness?

[Amy L]

Hello, I'm 19, and feel as though I am certain that I have some type of mental illness and I truly need help. When I was younger I had a voice that would be in my head sometimes. I can't recall what it sayed, but I was always terrified by it. Also, sometimes sounds are elevated still today as I sit alone in my room at night sometimes little normal sounds are unbearably loud and won't go away. Also, I am known to have drastic mood changes. I get very irritable for no reason and because of this I've been kicked out of my parents house and have trouble with my girlfriend. On the other hand, I can be extremely happy at times, it's weird. I have had suicidal thoughts in my head for several years now. When I get angry or depressed, I constantly think about death, to myself and others. I've sort of attempted suicide by putting a lanyard around my neck and hanging myself from a dooorknob, after a while, the lanyard broke and I survived. I also bang my head alot and am aggressive towards others. I have a poor outlook on life and need help, please.