I have a lot of difficulty getting wet when I want to have sex. Even if we have foreplay. most of the time I need to use lubrication, otherwise it is very painful to try and have sex. We've been together for 3 years and it's always been like this. Sometimes when we have sex, it feels like the head of his penis is banging something on my vaginal wall (not my cervix which he occasionally hits as well). So the combination of the dryness and the strange feeling of him banging something makes sex difficult and much less enjoyable. What could be causing this and how can I fix it? (I have been on birth control since we started dating, so I have no comparison to having sex on the pill and off if the pill is the problem.)