Tonight I noticed one of our golden comets looked a little off. She was shaking her head like she had a fly buzzing around. I sprayed them all down with poultry protector figuring she may have mites, but none were seen. I let them out to range and she was fine and scratching with the rest of them then suddenly she stood still and did not want to move. I picked her up and moved her back to the run and she went in a corner and laid down. She was closing her eyes and resting. When she does get up her tail feathers are pointing down. I felt her crop and it was about the size of a golf ball because she did eat when she first was let out. I tried gently feeling her underneath and it did not feel like there was and egg in there. Today we got 5 eggs out of the six of them but no way to know who layed and which didn't. No idea what is wrong, and I know these symptoms are vague, but I know she is not herself. Any ideas?