newton, you said you got this pain just through foreplay? what would happen if you masturbated? would you get this same pain? if not, then what do you attribute this difference to? is there something he is doing to you during foreplay that you don't do to yourself if you masturbate?
maybe you don't masturbate...i can understand that, but if you don't, you ought to give it a try to see what's going on.
please write back and give us some more information to go on and maybe we can help you.
jasmine