I'm new to chickens so I have no idea what else to look for but I have one chicken who is weak. She lays down all day close to the water. She is eating and drinking some. She started laying less frequently lately but I attributed that to molting. She's looking pretty rough right now. Also her last egg has a very thin shell but it's the only one she has ever laid. I have checked for fleas and mites and I can't see anything. Where should I start to make this girl feel better?