My Silver Wyandotte is being very lethargic, just sitting around the yard all day. She hasn't been running with the flock on our 2 acre property in the last 3 or 4 days. Head is up, alert and sitting like on a nest. Acting very calm and mellow. Comb is red, eating and drinking, no signs of wounds, infections, etc. Anything to check for or be worried about ? -Thanks