What Causes Frequent Headaches And Nosebleeds?

What is wrong with me? I get headaches and nosebleeds almost every day, I often feel disoriented and confused, I always want to be alone - I hate people talking to me, I find it hard to concentrate, I sometimes feel lightheaded or dizzy, often lose conciousness in the form of blankly staring and I talk to a voice in my head. My mood swings from irritable and volatile, to so happy I'm innapropriate, to so angry I punch through walls and yell and scream. WHAT'S WRONG WITH ME?!