Sometimes when having sex with my boyfriend, I experience a bad, somewhat sharp pain. It usually seems to be if we are doggy style, or if he is on top with my legs over his shoulders (sorry if thats too graphic). It's really only in these positions and only when he thrusts. It kind of seems like he is hitting something, like he's too deep. Is that what the pain is, and what exactly is he hitting? I would just really like to know; your knowledge is appreciated. Thanks.