Is my hen broody?

I've read about broody hens but don't know if this is what's going on or not.
I noticed yesterday that our 3 yr old Rhoad Island red was acting funny. She was all puffed up, looking really pretty and fluffy, and was making gurgly sounds. Today I found her on the nest at 7 am, and then been there each time I checked.. She was all annoyed, not her usual behavior, when I tried to approach her. The other hens laid their eggs on the floor instead of using another box. We got her off and she has been walking around like a peacock. Her feathers and wings are all sticking out like a male bird of other species. There were no eggs under her, but she has had issues with laying eggs for about 8 months. She sometimes lays soft shells or no eggs at all. She didn't go back on the nest after we moved her. not yet at least. That was about 30 minutes ago. Now she's laying in the dust with her sisters. Any advice?
Thanks!!!