Sex has started to hurt?

Hi so my boyfriend and I are long distance so we don't see eachother often. He was visiting for the weekend and every time we had sex it hurt. It hurt the whole time a bit like how it hurt when I lost my viginity. It didn't matter what position we were in either (though it hurt more from behind but even missionary wasn't too comfortable) We've been apart 6 months, but Ive gone longer than that without sex before and that never caused problems. Has anyone ever experienced this? I've made an appointment to see my doctor but that's not till next week and he's only here for another couple of days so it'd be nice to have sex without having to stop. Thank you!