My hen, Tep-tep, started limping yesterday morning. She seems to have pain (on palpitation) in her right knee. Should I just keep an eye on her for a few days to see if it goes away? Or is there something else I should worry about? She is a Plymouth Barred Rock, about six months old. We put a new door on the hen house last weekend, and I wonder if maybe she got her leg stuck in it or something. I certainly didn't find her that way, but it's the only thing I can think of that might have caused her to hurt her leg. The feathers on her butt are looking a little bit stuck together and poopy - is this what they mean by pasty butt? I cleaned her off with olive oil and gave all the chickens some plain yogurt. How concerned do I need to be?