I didn't lose my virginity until I was eighteen. I couldn't wear tampons until I was sixteen because it was just hard to get them in. I'm twenty-one now. But I just can't have sex in certain positions. Doggie style and from the side just don't work. I would consider my boyfriend to be average size, maybe a little larger than average, but still! I thought after having sex for two and a half years, I would losen up. What can I do?