Sex help..

Whenever me and my SO have sex sometimes I enjoy it other times I feel like I could be doing something else. Half the time I want to have sex so bad but soon after I would rather be watching a movie. I think that a lot of it had to do with the fact that it hurts when he goes in (but that's in certain spots). Is there something wrong with me? Can I fix this? I just want it to be enjoyable.