So, Pebbles puffed up and hissed at me a little bit earlier when I was checking to make sure she didn't have extra eggs. She didn't really do anything else though. I'm wondering if she can feel the eggs starting to wiggle under her maybe,and getting a little tense? Either that our she's sick of me checking on her lol.
I have found that when the poults are hatching or just about to hatch that my hens will talk to the little ones when I approach the nest. Before that they just sit calmly on the nest. I never bother looking for poults until I hear the hens talking to them. Of course that is also when the hens get nasty. I have pulled a bloody hand back more than once.
Good luck.