One of my hens is pulling her feathers out on her head and neck, well at least I think she is but all of a sudden she has little black stumps where her feathers should be. Is she moulting(its still winter) and she has also stopped laying eggs, she is only about 8 or 9 months old she only started laying in June. She also seems flighty lately she usually isi the sweet one who clucks around my feet when I'm down in the run, but not anymore, I'm worried about her. She is eating and drinking still.