What Causes Burning Sensation And Swelling In Vagina After Unprotected Sex?

I am a 21 year old female, 5'3" and way about 115lbs. Everytime my boyfriend and I have sex, unprotected or protected, my vagina burns and is swollen and raw. It will go away after a while but it never fails to happen after sex. My boyfriend is 22yrs old 6'6" and 230lbs and he normally never feels anything but just recently he started saying that his penis feels raw and bruised after sex. We are almost always extremely lubricated. This is making me afraid to have sex and I dont know what to do. I recently went to get checked out just incase and I didnt have anything. I have a history of bladder infections and sometimes sex is what causes them and that also makes me afraid to have sex. I do not know what to do or what we are doing wrong but this never happened with any other of my partners, nor with him. He is very healthy and athletic with no medical problems. Please Help!?