This has happened pretty quickly. My barred rock hen spent the night on the perch in the nesting area...shortly after I went out to feed everybody, she left that area and is now standing with her head completely drooped, almost to the ground, eyes closed. Probed gently--not egg bound. Did she get bit, ate something--what can I do for her? Throat looks clear...breathing normally. She is 3.5 years old.