I'd definitely got o a gynecologist and discuss this; you may have endometriosis or some other kind of issue down there. This isn't normal. Many conditions can cause pain during sex.

He may also be going too deep sometimes and brusing your cervix, which could cause extended pain and feeling like something is stuck inside of you.

see a doctor!!

I Dont Know What To Say I Find It Emabrassing ....
As Im Just 16.
I Might Go To The Nearest Family Planning Clinic"
See What The Women There Have To Say

I've had the same exact problem you are describing. I've even gone to the ER it was so intense. They found nothing unusual and said it could be cysts bursting from the activity. Also it could be he may be hitting your cervix which can feel just like what you're describing. I suggest you def. go see someone and describe whats happening. They are there to help with your questions and concerns, there's nothing to be embarrased about.