The deep green stool looks like she is not eating. There is mucus and white urates, and the second stool might have a little blood in it. I would take a sample into a local vet to look for parasites. Usually a 3 year old does not have coccidiosis unless they are weak and immune compromised, but it is possible. But if you want to start some Corid, that will not be harmful.
I would bring her inside to watch if she is eating and drinking. Offer some cooked egg and some wet chicken feed. Add a spoonful of plain yogurt to her food. Give her some Poultry NutriDrench a few drops up to 2 ml per day.
Feel of her crop to see if it is empty, full, hard, or puffy. Check again early in the morning to make sure it has emptied. Crop problems as well as reproductive problems are very common in hens over 2. Feel her breast bone for being more prominent to see if she has lost weight, and her lower belly between her legs to check if she is enlarged there. Let us know what you find.