Just found my Rhode Island hen on coop floor this morning. Very weak and can hardly stand. Sometimes she drops her head to side and shuts her eyes and I thought I lost her but she came back. Won't eat or drink. She was fine yesterday. I've isolated her but am not sure what's wrong or how to help. Tried to give water with syringe but she fell to her side like she died. Finally she was ok. I'm concerned she's too far gone and hope she wasn't contagious to the rest of the flock. I have never had a sick chicken. Help!?