Chicken lethargic, puffed feathers, one eye closed

[Crystalcatch]

New chicken mom here. We have five 10-week-old hens. Today our black star has suddenly been standing still in the corner of the run, feathers puffed. I noticed one eye has been closed. It will open occasionally. She’s been eating and drinking, but not moving most the day. I let them free range and she ran to be near the others, then ran back to the run when the others came in. That’s really all she’s moved today. I’m afraid isolating her in the shed or house would be stressful.
Any advice would be so appreciated! Should I bring her in the house? I put chick saver electrolytes in their water. Should I medicate her?
Poop is normal. No sneezing or coughing.
Thank you!

 

[Yardmom]

How is she doing today. Seperating is stressful to a bird, but if you need to watch her closely or have any reason to believe she is contagious sometimes seperating is nessisary.

 

[Crystalcatch]

Yardmom, thank you so much for asking. We brought her inside and let her warm up for a few hours (it’s been cold and rainy and they’ve only been outside for a few weeks). After a few hours she seemed so sad that we took her back out with the others and gave them all some treats. She ate happily and went to her coop for an early bedtime. The next day, she was fine! I wonder if she was just cold.