The frog is still alive and responsive this morning. Going by the tympanum size, I'm guessing female. I'm going to get a UVB light and a heating pad later today.

I'm actually getting a little excited looking at bullfrog care - I love aquascaping, but my turtle will eat everything I give her (including moss balls). Once the frog is well again, I plan on giving her a good home with plenty of safe plants and hiding spots. For now I'm keeping it simple and easy to monitor/clean.