Great news!I'm glad he didn't just put her on antibiotics, they aren't without risks. And no, you're NOT an idiot. I know I've picked up a snake that had
just drank water (without my knowing it) & had them spit it up on me. At least you cared enough to get her checked out. Sounds like you have a good vet there.
(he didn't, by any chance, have a guess as to her age, did he?)