Hey...Last Night Me And My Husband Were Having Sex, And

Hey...Last night me and my husband were having sex, and when we started doing deep penetration, i started to have a sharp pain, but it was only painful when he did deep penetration. I am on a low dose birth control for possible endometriometriosis. could that be one of the reasons? I'm just confused becuase this has never happened since i had surgery in september!