I have a sick hen Three days ago when I came home from work and fed the girls, one would not come eat and was standing leaning against a post with her eyes closed. I took her out and checked her for any wounds or mites. I couldn't find anything. I separated her and put her in a large dog crate in case she has something that could infect my other girls. I put some apple cider vinegar in her water and also put some Gatorade in there for her, along with food. She seems to be drinking and eating a little bit. Her poop is bright yellow. She lays down every chance she gets and is hardly vocal at all. Her vent looks maybe a little swollen and on her left side she has a very hard internal lump near the vent-not bones. I don't know any technical chicken terms but I felt the other birds and they don't have it. It feels like it could possibly be an egg? I've tried to research this online but haven't found anything that has helped. She is a golden sex-link, and I have one Americana. She is 9 months old. They are let out during the day to roam around the yard. We live on a lake and it's in the upper 50's during the day right now. I should mention that last week one of the other girls - an Americana chicken got a wound on her head and her eye was completely swollen. She stopped eating and moving around- I ended up having to put her down. I don't think she had a disease, it looked like she was attached so I do not think these are related. But these are the only two hurt chickens I've had and their illness/injuries are so close together Any help would be greatly appreciated. Thanks.