Is it normal for "strange" things to turn me on?

I have fantasies about murdering people & it really gets me hot. While Im having sex I have my boyfrend choke me,Is that normal? the sight of blood gets me wet. I have a huge knife fetish I think its sexy. Danger is sexy. Is it normal to feel this way about things? I've always wanted someone to cut me while having sex,All bloody & wet. I dont really see anything wrong with it as long as no one gets hurt or I dont attempt anything.
Any comments/advice.