This is the first year of having chickens. I am currently wintering 10 hens. For the last three or for days I have 1 hen that just lays in the nesting box. It is apparent she does come out to go but than she goes right back in. When I move her to check for eggs she pecks at me and I do not find eggs. She is not interested in the"treats" I take out each night either. "Treats" being any fruits or vegetables I have in the house. I do not know what to do for her, let alone what may be wrong with her. Any advise would be greatly appreciated. Thank you.