pain during sex

I started having sex with my boyfriend in early November (he was my first, it hurt a lot the first few times) and then we didn't have sex again until mid-December (still hurt) and only had about a week before we went home for break and couldn't have sex for a month. Fast forward to after break and it hurt a lot again to have sex, but we did it almost every day and it got better. Even now it still hurts at the beginning for about a minute and then it's okay but that's only in two positions. I know he likes doggy and I also wanna be able to do other positions but it's painful, how can I make them (specifically doggy) less painful? Currently we can only do missionary (can't even put either of my legs over his shoulders) and me on top (I can't really sit up tho or it hurts). Please help!!