Also, was this wheezing sound actually coming from her mouth? When I have my snakes in a bath, they often get it in their nostrils, and so that's where the sound is coming from. Is that the case?

Some part of me thinks that it's not unusual to see bubbles in the back of their mouths, could just simply be some saliva. You know, like if we open our mouth without swallowing prior to doing so, there'll be some spit.:p

I know that a lot of people bump up the temps a little bit to fight off an RI at the first signs, so if you're worried you could do that.(:

Sooo yeah, I am from from an expert, though. ^-^