Have a RIR going on 3 years old combe turning a deep dark red and she is not eating well . could there be something wrong?
Just because of her age, she may be laying internally or could have egg yolk peritonitis, cancer, or ascites. Many of these hens will walk more upright, or like a penguin, and lay down a lot. They can suffer labored breathing. They are not many treatments that can save the life of a chicken with those illnesses. I would feed her some chopped egg or tuna to coax her to eat, and try to keep her comfortable. If she has fluid in her belly, some can be removed by draining with a needle occasionally to help breathing. A vet might be of help with a diagnosis, but of course is expensive. When and if she gets too uncomfortable, I would euthanize her. Here are a couple of links about ascites and internal laying: