I think you should act sooner than later. The labored breathing, etc. is going to be toward the end of being able to get her effective treatment in time. Waiting will make things worse.
Even if the vet has SOME glider experience he should be able to look up (with your prodding) the correct dosage of an antibiotic to clear the infection. I have had these symptoms from a rescue glider, he was under weight, unfortunately it did not turn out well for him.
You're being vigilant in noticing and getting her to a vet. Gliders hide their illnesses for as long as possible. A natural defense in the wild to not seem more like prey than their tiny bodies already suggest.
Best of luck. Keep us updated!!!