Is she in the nest at night too?
If you take her out and put her on the ground does she drop right back down into a flattened out but fluffy pancake?
Does she then go cluckcluckcluckcluckcluckcluck real low as she makes her way back to the nest?
Those are sure signs of a broody hen....I can hear that clucking starting before she even goes to nest.
Here's how I break broody hens:
My experience goes about like this: After her setting for 3 days and nights in the nest, I put her in a wire dog crate with smaller wire on the bottom but no bedding, set up on a couple of 4x4's right in the coop with feed and water.
I used to let them out a couple times a day, but now just once a day in the evening(you don't have to) and she would go out into the run, drop a huge turd, race around running, take a vigorous dust bath then head back to the nest... at which point I put her back in the crate. Each time her outings would lengthen a bit, eating, drinking and scratching more and on the 3rd afternoon she stayed out of the nest and went to roost that evening...event over, back to normal tho she didn't lay for another week or two. Or take her out of crate daily very near roosting time(30-60 mins) if she goes to roost great, if she goes to nest put her back in crate.
Chunk of 2x4 for a 'roost' was added to crate floor after pic was taken.
Here's
how I kit out a crate.
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