Your cervix is located right inside your vagina. It moves at different times of the month and during pregnancy. This is what you are feeling. Different positions will help with this kind of pain.

This happens to nearly all women at some time or another. Change positions, don't go in so deep, etc.

There could be a number of reasons that penatration would hurt. You need to make an appointment to be seen by your GYN. It may even be nothing, but still should be checked out.

There are so many other reasons why it could hurt other than early pregnancy. I've been with my boyfriend for two years and there's still times he goes to deep and I have to push him away. You may not be lubricated enough, that can hurt. I'm pregnant right now and it does hurt alittle more than normal but It's probably me just being paranoid. I can't tell you exactly why it hurts but try diffrent postions and maybe lube. Hopefully you figure out what the problem is.

If you can't figure it out, go see the doc. Painful sex is a symptom of various more serious conditions.

Personally, around my period, I can't have sex in certain positions because it really hurts. I've read that right before your period your cervix is more sensitive, maybe this is it?