Our 1 1/4 year old RIR hen was breathing harshly this morning and over a few hours has progressed to a sort of trumpet-like noise. It sounds like a failed note. She's opening her beak to breath, and is sneezing. It seems to be made every exhale. She was fine last night. The chickens have free roam of the backyard. She is lethargic and stands still, making the quiet trumpet noise. Her comb is red, maybe a little more than usual. Her eyes are clear and there doesn't seem to be anything else wrong with her except the sneezing and loud breathing. Her crop isn't squishy or swollen. She's holding her wings at attention. Her vent is clear. The noisy exhale gets worse when she is stressed. She's a pet, and we would really like to know what's wrong. Any suggestions or other info I need to give?