I think you handled that perfectly. If you don't feel comfortable, don't do it. The added benefits are that it adds mystery to you (most men probably don't turn down a woman's offer to have sex) and shows that you aren't just going to do things on her terms.
Bravo to you dude!
Me:38 W:39 No Children BD: 5/13 EA/PA Confirmed: 7/13 W Moved out 12/13