I have the same problem. You just have to get used to it, and it gets less after doing it many, many times. My BF is huge, and my mouth is not. The biggest problem I have is the jaw tiring, and the biggest problem he has is that I cannot always keep from scraping him with my teeth no matter how hard I try. His dick is so thick that it pulls my lips from off my teeth when he pulls out. When we finish, my jaw and throat hurt. Sometimes for a few days... But is is worth it.