Yeah, BD'ing (baby dance) - just another silly abbreviation/creation. It took me months to figure that one out.

If you're going for it every second to third day I wouldn't worry about adjusting your habits. As AJC said, it may be a good idea to chart/track your cycle so you know where you're at (and so does your doc should you ever need to seek advice), but it's certianly not compulsory. There is stacks of info on BellyBelly about charting and tracking and all sorts of stuff to do with TTC, so have a look around and see what suits you.

As for your concern that your husband might feel like a baby making machine if you do change your routine - chances are that as a bloke he really wont care but talk to him anyway. In any event it becomes a little bit mechanical I guess for some couples whilst TTC. Perfectly normal in my opinion and nothing to feel guilty about.