don't worry, I have been doing this now for a year and still haven't gotten comfortable wearing things that are a little more risky than I would normally wear. Doms love it when you are uncomfortable, certain sort of pleasure for them; I think. Anyway, if you did get comfortable he would just find something else more daring for you to wear.
Wear the clothes with little sass though. One thing I learned with Sir....he likes it even though I don't. It's enough to know that he likes it and leave it at that.
Sir loves when I go braless; I don't. Once I wore a bra because I really didn't like the braless thing....to shorten the story I ended up without the bra and my coat and it was cold out too. Thank God for warm hugs and other things.....