if i could offer a bloke's point-of-view. My OH doesn't climax from vaginal penetration. Stats suggest that is is common to maybe 60-80% of the female population. In our relationship sex is pretty much anything that involves at least one of us having an orgasm with the other one there. Sometimes she does it herself while I watch, sometimes I do it for her with a vibrator or fingers or tongue. Sometimes i get finished off by hand, sometimes inside her.
Just pointing out that sex doesn't have to be penis-in-vagina even from a man's point of view!
A good blokes point of view made too, quite right. But it's nice to be able to have penetration and to feel comfortable.
Sounds like it could be a tilted cervix, certainly worth getting it checked out, and yes Dr's have seen it all before!