I slept with my first cousin and I did so knowingly.
Why would you do that?
It was my first time, I didn't know that it would hurt me
You shouldn't be having sex with a relative like that. Having sex with a cousin is wrong and incestuous.
I understand that but I don't care
You should think before you engage in this behavior again as having sex with your cousin is immoral. I understand that you're tempted, but this behavior is wrong and harmful. Try to find someone appropriate to being in a relationship with.