Slow lethargic chicken not eating help!!!!

[Geordonbuck223]

I have a buff orpington hen that was at the fair Bout 2 weeks a pho I started. It icing a few days ago that she was moving slower and weak and that she wasn't eating or drinking! I feed her some mashed up tomatoes and some mushy chicken food she ate some! What could be wrong please help ASAP her poop looks like this

 

[Eggcessive]

How old? Could she have coccidiosis? Here is a link about it, and diarrhea is common, but bloody stools only occur sometimes: http://www.the-chicken-chick.com/2012/12/coccidiosis-what-backyard-chicken.html