If he really cares for you, and is deserving of your V-card, he will not be uncomfortable or judge your performance like that. If you feel that is a real risk, and that he will be scrutinizing you, then he’s not the one you should have your 1st time with.
If anything he should be the one trying to make sure you’re not uncomfortable in this situation. Your sexual experience is of great value (even though I don’t know who you are, I’m sure it is) especially your 1st time, and he is lucky to be graced with it. I’m sure your very considerate but you need to make this more about YOU and not just about him 🙂
What do you think?