My boyfriend and I have a really good sex life, when we first starting sleeping together was amazing but as time has gone on I think he's gotten more comfortable and he's become a bit more 'enthusiastic'. Sometimes when he goes too hard it hurts a little, I told him and he tried hard not to because he does really care but I think sometimes when we're really into it he forgets, I don't know how I can politely tell him in a way that will get thought to him, won't make him feel like he's doing something bad because he doesn't mean to but also doesn't kill the moment... Any ideas?