What’s wrong with me?

So whenever my boyfriend fingers me it hurts like hell, and he barely gets in there.

I tried doing it to myself and it feels go at first but it just hurts after,

It’s like a stinging and I just want to know if it’s just me or if it happens to other people and how I can prevent it. I’m quite tight, but I don’t know if that has anything to do with it.

I have never had proper sex and when I masturbate I use clit stimulation.

Also sometime I get a small stomach ache after.