Is my hen trying to go broody?

I have a little buckeye hen and it seems that she may be trying to go broody. she does not attack me or growl she just fluffs up her feathers when i get near her no matter where she is. she is the only chicken that lives in that cage but we have 3 roosters right next to her. could this be part off the problem? Yesterday i found her fluffed up on her nesting "box" (we use a bucket for her) after i had colected the egg she had just laid.is she trying to be broody or does she not like me anymore?

She may be broody. My broody hens never attack me, they just grumble, puff up and cluck.

Why is she all alone? It's better to have one hen alone than one hen with three roosters, but still, hens like a flock.