relationship advice (please help!)

So ladies, I need some advice. I am just a couple weeks shy of 18. I have been in a relationship with my best friend for about 6 months(I know, not very long-term) But we have been friends for about 5 years. He is super adorable and amazing and so kind and I love him so much. He makes me feel like I'm really worth something and that I'm really really attractive. But I have a lot of self-esteem issues and I automatically get into the mindset that he is only saying that to get in my pants. But I know him really well and I know that is not something he would do. However, he has had a lot more experience than me. By that I mean, he's slept with about 20 girls(that I know of) and  gotten oral from an additional 7. I did not have romantic feelings(or didn't know it) before we started "Talking". I am a virgin. Plain and simple right? Well I know he is getting really frustrated and I just need advice. I'm starting birth control on the 14th but how do I know if I'm ready to have sex? I'm worried I'm not going to compare to all the other girls. >.< 😔