I just wanted to post and update. I ended up taking my sweet Margarita to a vet Christmas Eve morning. I thought she might have had a respiratory thing going on and some antibiotics would do the trick. They took her in back and put her on oxygen. She couldn't even stand and was barely awake. The Dr. came back and said she was pretty sure she had Reproductive Disease. She said that is very common in birds 3-4 years of age. She was not egg bounds, at least neither her or I could feel one. She said it was not respiratory because she heard no wheezing. She did have some stuff in her crop. The Dr.'s explanation is that her body was probably shutting down there for not allowing the chicken to process for as normal. I've owned chickens for about 3 years now and had not heard, or run into, reproductive disease. Just wanted to post in case this info helps someone.