If you went down on her? And see the doc? Was she in the porn industry perhaps and thus required to get tested after unprotected sex (which technically getting head from someone is and it can transmit stuff like herpes)? That’s the only explanation I can come up with and if so then you could’ve asked if she’d need to see the doc if you had sex without going down on her, or used a “condom blanket”. Still I’d see that as a business expense on her side and not something you should pay.