I once intentionally ran over an armadillo in my truck at 60 mph to impress my friends in high school. You could hear it bounce up and down under my truck like listening to someone dribble a basketball in fast motion. The thuds were awful. I'm 32 now. Still feel sick about it.
That is awful. Have you ever done anything else as bad as intentionally hitting an animal?
I have never done anything else that made me feel that way. It was awful.
Well, it's clear you know that intentionally hurting an animal is a terrible thing to do. You have to live with the feelings, and you'll never do it again, so that's good.
True, I never got over it, nor had the desire to do it.
If it's hard to get over maybe you should talk to someone about it so it doesn't eat you up inside.