Most any breed can go broody.She makes the sound but that’s the only thing, are EEs normals broody?
You should never leave real eggs in the nest overnight, collect all of them daily.I usually only see her at night on the egg once in awhile and I take the eggs out from under her as soon as I can so she doesn’t sit on then
If she sleeping in the nest at night she could be broody or not have enough space to roost with the flock.