Is there something wrong with me?

I feel like I am crazy, I feel like I KNOW that I am crazy. I don't do or say anything to prove this because I don't want to lose control of myself, but sometimes I feel like there are two voices in my head. One voice tells me what I want, and the other side disagrees and tells me what I want myself to want. I can never figure out what I actually want or who I actually am. I get very moody, some days I am very happy and peppy while other days I become very depressed. I get very paranoid sometimes and I used to cut myself to calm down but I stopped because I know that my cuts worry my boyfriend. When I tell people this they think I'm fine and that these things are normal but I feel like there is something more inside of me that will overtake me. I know that I am not sane, I just don't know how or why.