Pain after sex?

So I haven’t had sex in a while, two-three weeks maybe. I just had sex about an hour ago and the sex itself was great and I experienced no pain, but shortly after I went to the bathroom and i realized how much it hurt.. it wasn’t too much of a burning feeling, but almost a sore feeling mixed with a little bit of burn. I know you can get sore after sex I didn’t think it could be this quick? Also, I have sex with the same person and I usually don’t get sore afterwards. Just curious on if I should be worried at all !! thanks much xx