Pain During Sex

Hi, so I already have a doctors appointment scheduled to discuss this but I wanted to see if I was the only one or if someone could relate. Sometimes, I’ll have sex and be perfectly fine, other times it hurts so so bad. Lube isn’t an issue that’s what my last gyno told me, it’s pain similar to period cramps, and it’s only sometimes. Usually it’s times when I’m having sex multiple times a day or over the course of a few days, the later ones will hurt so bad I can’t even continue. I just want to know if others feel this and maybe know what’s going on?