I came home from work and checked on the girls, and one was on the floor of the coop, head down, lethargic... not moving or peeping. I picked her up, made a gallon of fresh water with Save-a-chick and Probiotics mixed in... dipped her beak in it several times to get her to drink. She seemed to drink a little, but then head down, almost floppy necked. I am freaking out here... these are my first chicks and I just don't know what I did wrong. I feel TERRIBLE and NEED HELP!!! What else should I be doing?!? What would cause this?? She was fine this morning when I let them into their enclosed, fully covered pen area. The other chicks are all acting fine. PLEASE HELP!!