Do you think there's a chance that you may be asexual? For an asexual person, it's perfectly not to desire sex at all. Regardless, you should explain to your boyfriend that you're uncomfortable, and that you're not ready to have sex yet. In fact, you might not ever be ready, and if so, that's okay. Everyone's different. Just don't do anything you're not comfortable with. Any sex that you have should be something you want too, and on your own terms.

-CW