I have recently began a new relationship. The last time I had, prior to this relationship, was March. I've had an STD check, everything, and all was well, so I know it's not that causing painful sex. It's not always painful either, just penetration (I'm well lubricated as well) and then I guess I relax and it's fine. We also go for hours, so perhaps my soreness is from not being used to going for that long. I'm not sure. Has anyone experienced pain for a few days after? I should also mention I've got hemorrhoid's, which are also sore afterwards as well. Perhaps the pain is from those.