Chicken panting all night even in comfortable temps

Our 10 month old Easter egger Daffodil started panting in the coop around 8pm - at first I thought she was just hot so I moved her to one of the outside run roosts. I checked again at 11pm and she was still panting and with her wings drooping.

I brought her inside in a dog crate and this morning she had pooped normally and her crop was empty, but still panting.

She is eating and moving around normally but she is clearly having trouble breathing. Sometimes she stretches and flaps her wings like trying to get a breath.

She had a messy poo yesterday before the panting started and I washed her off, and she did start panting after that but they do that when they’re stressed.

Her poops are totally normal and she seems to be acting normal except tired (laying down) and near-constant panting.

We sadly lost a chicken 5-6 days ago while we were away on vacation and a pet sitter was helping. That chicken had diarrhea for a few days and then got pneumonia. The vet said likely she had some internal blockage that prevented her crop from emptying and she had aspirated some water. I think it was a genetic problem internally.

It may be that this chicken has a respiratory infection but I don’t know what to do to help.

Should I continue to keep her separated? It would be awful to lose another.

I’m reluctant to take her to the vet since it’s $200 for the exam and I’m not sure what they would do if it’s viral.

Any advice would help a lot…