There are many ways people might not be sexually compatible. He was incredibly insecure about it at first until I made it clear that he was great at getting me off in other ways. He had told me that his parents took him to see doctors because of his lack of development. You can learn 24 other sex positions where you are lying on your back here. The main issue was with protection, as regular sized condoms tended to slip off — but I got on the pill soon enough, and the sex has been great since.