Sex hurts

I've had sex with my current boyfriend a couple times but it really hurts and sometimes he hits this spot and it hurts to much. I'm not a virgin, I've had sex with two other guys it hurt so bad when I lost my virginity and before that I had trouble fitting a tampon in me and with the second guy we only had sex once but we had trouble getting it in but once it was we where fine. Any advice would be helpful.