What Causes Pain In The Vagina After The Intercourse?

Me and my boyfriend have been having unprotected sex for the past 5 months. I love him, no problem with getting pregnant but lately whenever we hve sex after 10 minute or so my vagina hurts that any little movement of his penis will hurt. So i have to tell him to take it out... so what do you think is the problem, and after i go pee, it hurts alot. sort of like a sting sensation on my vagina