I have a 10 month old new Hampshire red that has started shaking her head back and forth. Not like a "no" shake but more like a ray Charles sway thing. It has been below zero at night and I was wondering if this can be from the cold? Her comb got a little dusky and tiped with black so I did the Vaseline thing. Is it a pain response to frostbite? No ear mites I can see. Can mites even live in below zero temps. All other chickens seem ok. She didn't roost with them the last 2 nights. She slept in a nesting box. Last night was about -10. But the first night it was about 15 degrees. I guess other recent change would be that they have been more interested in staying in the coop. My run is covered but some snow got in and they are not a fan. Their main food and water is out there. I put smaller ones in the coop to make sure they get fed but I want them to go out and not be such wimps. They live in Wisconsin and it gets cold so they need to be able to deal, and from what I have heard they should be ok in cold as long as they have good ventilation and no drafts in the coop. Any ideas about the head swaying?