It means he's going too deep most likely!

The feeling is probably caused by his penis hitting your cervix. Make him use shallower thrusts.

what does shallower thrusts

go slower and not so deep

oh thanks

Yes, exactly. Don't let him push his penis in so deep. He can still go fast, just not deep.

do you achieve orgasm when you have sex? because it could be uterine contractions. another thing to check out: if you've ever had an sexually transmitted infection (chlamydia, gonorrhea), you can get something called pelvic inflammatory disease. this _needs_ to be treated with antibiotics to prevent more serious problems and protect your fertility.

see your doctor.