Poor lovely. I, too, suspect a reproductive disorder. BUT, she could have an infection of some kind taking its toll, and it might be worth a round of antibiotics if veterinary care is not an option. I don’t recall if it was @azygous or @rebrascora, but one of them had a chicken fall ill from a stagnant compost pile, resulting in a bacterial infection and bloated abdomen, among other things, I think.
One thing the vet should be able to do for you, even if they don’t treat chickens, is perform a fecal float.
One thing the vet should be able to do for you, even if they don’t treat chickens, is perform a fecal float.