My older Buff Orpington hen hasn't been herself lately. She stays in the coop, stopped laying (But I figured she would soon since shes 5 years old and was an awesome layer for 4 years) She doesn't come running up to me like she used to after school and wont listen to the rooster's dinner calls. And she has stopped free ranging and seems to be doing a lot of squatting and just standing still, maybe there's an eggs stuck or something? And yesterday I picked her up and she was breathing quite heavily and had her mouth open and wasn't clucking or making noise and when she did it was a kind of high pitched noise. She seems kind of depressed too I really hope she isn't choking on something I don't think I could afford a vet bill for an old Hen, but shes special to me because shes the only chicken that survived our 60 below temperature last winter. Anyone know what could be wrong? Thanks.