Sick chinchilla!!!😭

My Chinchilla is breathing very heavy, I nocitced about 2 weeks ago that he was breathing faster then normal, but the next day he was breathing fine so I just thought maybe it was from running around. Now the past 2-3 days his been breathing heavy again but this time he's breathing hard all the time, and it seems to be getting worse. I'm almost certain it's some kind of lung infection. So I haven't gave him his dust bath cause I didn't want to make it worse before I could see a vet. He's acting completely normal still bouncing around eating and drinking, etc. I don't know what caused him to get sick. He's only a year old, he's eats Oxbow pellets and Timothy hay. He gets a dust bath every 2-3 days.He gets lots of exercise, and he runs on his wheel all night. The room temperature is about 20-25 degrees Celsius. He has a appointment tomorrow at 4 o'clock. But I'm so scared. I feel like I have to constantly watch him to make sure he's ok. Can someone please let me know if this happened to anyone's else's chin. And what help it.😭😭