We have 10 hens. One of the hens is a Black Star. None have started laying eggs yet. We introduced a young but older rooster to the flock a couple weeks ago. Since then this Black Star hen has been displaying some weird behavior. She shakes her lower body and stomps her feet. Thought it may have been some kind of injury but can't find anything. Maybe a disease, but I don't think so. Maybe an egg she can't get out, but that also doesn't seem to be the problem. I have heard it could be that she is submitting to the rooster or the dominate human. Sometimes she walks around fine but most of the time she is displaying this behavior. Any thoughts?