I can't go on top

Basically I am a massive pile of nervous during sex, me and my boyfriend got into a routine of him giving me oral then us doing missionary and that was it, I can tell he wants more though and I do too but I'm just nervous, I tried going on top and I just couldn't get a rhythm going, we had to go back to missionary because he needed to finish. I'm totally not up for giving a blowjob either, I'm just not keen at all (I've told him he doesn't have to give me oral but he insists) we don't have sex very often so I'd like it to be special!