Haha! I dunno, I did have a silent broody once, but I had to break her because she wanted to sit in my gigantic burn pit for some reason, and there was no telling what could have been lurking underneath her. Maybe she's halfway broody! Haha!
No kidding!
Sounds to me like she was just "stretching"! Maybe she's broody? That's not how my broody acts when I pull her off the nest, but it is how she acts when she gets off by herself.