Is there something wrong with me psychologically?

I'm not quite sure what to research and I'm afraid to go see a doctor as I'm only 16. I believe I may be bipolar. One day I can be fine, I'll laugh and make jokes and get along with people. However other days I feel like I'm not wanted in the world, I stay in the house and I freak out at anyone who tries to talk to me and I also hold grudges against those who are laughing without me. These are frequent and continuous actions. I often get jealous of people really easily, mainly because I'm not included in something I wasn't even interested in. I cling to one person for a short amount of time and get jealous when they go off with other people. I was depressed last year, I often enjoy being alone and I feel the world is against me. I abuse the ones who love me and sometimes I don't think I can feel for people. I'm hostile and horrible to my boyfriend, yet he is the most amazing person I've come across. Tonight I freaked at him, I hit him, scratched him and punched him, and screamed at him to go home, even though he did nothing wrong. I only did it because I didn't want him to go home. I don't know what's wrong with me, but there's something thats not at all normal with me..