Burning?

My BF stopped pulling out to finish about 3 months ago. Since then, I've noticed that my vagina and labia have a burning/swollen sensation for 1 or 2 days after sex (especially when wiping). I've been tested for STDs so it's not that. Has anyone else had this happen? I'd like to have more sex, but I can't bring myself to do it until the burning feeling goes away and I feel normal again.