I understand exactly how you feel and I know how hard it is when you are unhappy with how you look. The first time is never perfect and when we are self conscious it makes the experience even worse. I do not really have any advice for you except I can tell you about my own personal experience.

I was so shy about my body and sex while the guy I was with was not even my boyfriend and he had little regard for how I felt. He wanted to leave the lights on and I wanted the room to be as dark as possible. It turned into an argument and he called me uncooperative and childish. When I would not uncover myself with the lights on he got impatient and pushy, so we did it with the lights on and since he was unhappy with me, he made no effort to be gentle and it only lasted a few minutes.

So, before you do anything learn to be happy with your body and that he is respectful of it. If you would feel better without lights let him know and really insist and for your first time you will probably be on your back so do not be too self-conscious about that.