Update:
I brought my hen to the vet this morning and they had a look at her. They could not find anything physically wrong with her. There were no signs of any lice, mites, or parasites. They did agree that the behavior I told them about, was that of a sick hen, so they were a bit puzzled.
The only thing the vet could see was that my girl was a bit underweight, and they said it could be a virus making her feel under the weather. The small stye on her is nothing to worry about.
They gave me some worming medacine to give them to be on the safe side even though there was nothing found in the poo sample.
My hen seems to be acting a lot better at this point, but when I saw her on the floor of the coop this morning, my heart sank.
The vet asked me to call them tomorrow and let them know how she is doing.
On a good note, the vet says I am doing a great job with the girls.
I am hoping this is a happy ending
Anyone know how I can fatten up the girls? Right now, they get layer mix and scratch with lots of BOSS. They have oyster shell mixed with their food. They also get daily treats when I go out to clean things up and change their water.