im a really shy guy too, and pretty much the same as u in bed. i rather be submissive, but first of all.. if u dont like it, then dont do it, but make sure to tell him that u dont like it.

if u do like it, or want to do it for him, then do it, but tell him that u dont want to do it everytime, cuz i know u wouldnt like that.

also, maybe you could suggest some things for him to do for u too. maybe be more dominant on his side. just a comment.

but hey, it's ur life. but personally, i wouldnt do what i didnt like. i know u want to please him but set limits. on the other side, this could make u less shy (to him) and u could become more comfortable. who knows. good luck with everything tho.