What is wrong with me?

Ok. So I know I'm weird but I don't think that this is normal.

I was standing outside and my Dad told me to cut some rhubarb because we were making a stew type of thing and my Dad handed me this knife to cut it to me. So I sat down and I was cutting it all like normal when my Mum sat next to me. All of a sudden I had the weirdest feeling that I wanted to stab her, as much as I tried to stop thinking about it I couldn't so I just dropped the knife and left. After that day I keep getting that same impulse to stab or break things even if the people I'm wanting to stab are completely innocent and have done absolutely nothing to upset me.

I also hear voices often and have a strong interest in murder, usually it's wanting to solve it but sometimes it's actually committing it.

I've been told many times that I show no emotions. I never cry and I never see people as having feelings. I always think they're just people and never understand when they're hurt or upset.

I definitely have problems when it comes to telling the difference between reality and imagination. I even make up my own characters in my head that I believe are real.

I also don't have any hobbies apart from movies because I believe they are weaknesses and whatever hobbies I take up a threat will use to threaten me with.

By the way Im 14 years old and a girl. Is this normal???? I don't think it is but that's just me. Please help!!!