I've been seeing this girl a few times and the other night she asked me to have sex with her. She's stayed over my place a few times and we both know she is a virgin (although at 21 it seems incredible). She could only get a little bit of me in on our night time session and had to stop because it hurt, in the morning we got more in and I must admit it felt fantastic, we used a lot of lube but she still hurt and felt nothing nice at all. The shape of my cock and the way I use it, I can always find a girls "sweet spot", rather unashamedly I'll admit that, but how long does it take to become sensitive to sex? She thinks that it might get better the next time we do it, and I suggested to her to do kegals and touch herself to find out what she likes best. Any other ideas?