You can Google for it, but passing gas from the vagina is the first symptom that Brassard warns about.
However. If you aren't sure whether that's what happened, the odds are very good it didn't; also, so long as you don't have actual feces leaking from the vagina or a high fever, you're likely fine. It can't hurt to see a doctor if you're really worried, but it's probably nothing.
(The one woman I know who actually had a fistula, was able to see the feces oozing through a hole in there every time she had a bowel movement. It wasn't subtle or easy to mistake what was wrong.)
Oh, and the nurses said that if a fistula hasn't happened in the first week - while you're still at Aesclepiade - it almost certainly won't, and never has to any of his patients yet.