Ready or not for sex

Hey girls, I'm really struggling at the moment. My boyfriend and I have only been together for four months and sex has already appeared in the cards. He and I both want to do it but I continue to chicken out. I don't know if it's because he's still a Virgin and I'm not so I feel like he's expecting it to be absolutely amazing first time. But then I also don't know if it's me... The last guy I slept with left me a few months and then a few weeks after we did it. Is that a reason to be afraid? Someone please help!