Sex positions

Kaylee
Okay, my boyfriend and I have a really great sex life for our age. We've only really tried 2 positions that work for us. My favorite position is doggy style but the position isn't working for us. My boyfriend, he has a smaller than average penis. I wanna say it's about 5 inches hard. Is there any reason why the position isn't working for us? Is his penis too small? Am I too large? I'm not really sure how to make it work for us