Going through something similar. My guy had an RI that we did a course of antibiotics for and 12 days later, still gaping and taking big, deep breaths. Some days he has stringy saliva. Other days he doesnt. No nose in the air breathing. I am at a loss. Round 2 of vet visits is today. Up until this morning, he had still been cruising around, eating well, basking and pretty active. Today, it's almost 1pm and he's still tucked in with his tail curled in the lower part of the cage. Eyes open and alert, just not moving around. Hoping the vet has some insight today. I hope your guy is feeling better.