Thanks for the pic. Her poop looks normal. Check her crop to see if it's full before she eats tomorrow morning. If it's full, she might have an impacted crop.
Basically she is acting lethargic. It could be coccidiosis but it isnt that common that it would overwhelm a one year old hen. Worms are a possibility. You could take a fecal sample to a vet and have them look it under a microscope for coccidia and worm eggs. Coccidia will always be present on the microscopic slide. However, if the slide is loaded with coccidia oocysts, then there is a problem and she will need treatment.
Another possibility could be external parasites. Inspect her for lice and mites, especially around her vent area.
Lice are white, off white or straw in color. Lice eggs can be seen on feather shafts.
Mites are bloodsuckers, cause anemia, then death. They are black or red in color and have 8 legs.
Let us know how it goes.