Holding her wing down

[KikiDeAnime]

I'm unable to catch the hen but I noticed she's holding one of her wings very low on her side. I'll try to get video of her and post it below soon.
While looking at her, I didn't see any blood anywhere even when she moved it slightly.

Can someone list all the reasons/causes for this just to give me an idea of what could have happened??

 

[sourland]

She may have just strained her wing - it happens. Or there may be a significant injury.

 

[KikiDeAnime]

She may have just strained her wing - it happens. Or there may be a significant injury.

Think you're right about straining her wing. She's not holding it down today.