Hi
@Flockontherock 
Sorry to hear your hen is not feeling well.
How does her abdomen feel - any bloat, fullness, etc.?
When was the last time she laid an egg?
As
@aart mentions, it does sound like an impacted, slow or sour crop. Crop issues can be a symptom of an underlying condition like internal laying/reproductive disorders, worms or cocci, so having a fecal test would be a good idea.
Since she has been in the same spot for a couple of days, she may be dehydrated as well, so try to get some fluids into her. Once she is drinking, then offer wet feed, eliminate anything hard to digest at this time (scratch, corn, etc.) and give only wet feed, yogurt, chopped egg, etc.
This is one of the best articles about crop issues that I know about, I recommend that you read it completely before trying any treatment options, if you have a vet that can see her that is always best.
http://www.backyardchickens.com/a/impacted-slow-and-sour-crops-prevention-and-treatments
Keep us posted.