I have a hen that got attacked by another hen. She got pecked on the head then several Roosters attacked her also. Her eyes are clear, but she sleeps alot and throws her head back onto her back and shakes it vigorusly back and forth. I have brought her into the house (weather has been very cold) given her water by eye dropper and some apple sauce. very little is all she will take. When she trys to walk she falls down and walk sideways. Any ideas and what does the shaking and bent head and neck mean?