Hell's Servant

I was just a normal girl with a life and friends. I don't know what happened. I felt a cold shiver down my spine. Suddenly I felt full of something. I had been possessed by something. I couldn't speak or move. I had no control over my body. I saw myself in the mirror. My eyes were black. Now I am trapped in my mind with this creepy voice lurking and controlling me. I've hurt people. I've killed people. When the demon leaves I can move. But I see them lurking behind me where I go. I cant escape. I've become a personal servant of someone I don't even know. They just possessed me. now they never leave. what's happening to me?