Welcome To BYC!
I'm sorry to hear about your hen.
The normal body temperature range for an adult chicken is 105-107 F to me it doesn't sound like she's got a fever.
The vet only gave one dose of Baytril? Did he send more home with you to follow up?
"Normally" Baytril is given for 3-5 days.
Is your hen able to poop? What does that look like?
What you describe for this morning, she is having issues with her crop. Does her breath smell bad - yeasty or fermented? If it does, then Sour Crop. If there really is no odor, then you could be dealing with an impacted, doughy or slow crop.
You don't mention when your hen last laid an egg? When you examined her, did you notice if her abdomen was bloated or felt like it had fluid in it? Often crops issues are a symptom of an underlying condition - worms, coccidiosis, infection and reproductive disorders are common conditions that accompany crop issues.
Read the article below to see if one of the crop problems sounds like what you see/feel - report back to us with your findings along with some photos and we will go from there.
http://www.backyardchickens.com/a/impacted-slow-and-sour-crops-prevention-and-treatments