Painful sex?

am 20, and me and my boyfriend have been having sexual problems lately. Sex is very painful for me. Usually it gets a lot better about half way through, when i get wet, but before that, it basically feels like when you repeatedly bang into a sunburn, which lol i know isnt possible, but it hurts alot and that is the only way i can think of discribing it.

We dont have problems with other things, only this. I find him sexy, he turns me on, i turn him on, but for some reason, even if i am very turned one, i still cant really get wet enough to make it hurt less. So the amount of foreplay doesnt seem to help me. Ive watched porn together, given each other oral sex, and done many things to get myself going, but nothing works. And even when i am wet, some areas/positions still hurt.