Pulsating vent, feathers puffed, standing alone

[waterbebe]

Need some advice...direction...a few days ago, my hen came out of the coop all puffed up and stood by herself. Today, she is out, but standing still by herself. Her feathers are all puffed up...and her butt seems to  be pulsating. She is drinking water and food, though. Has not laid an egg for a few days, however. Her vent is also clean. Egg bound perhaps? The other chicks are fine. They do have small case of leg mites, which we are treating with oil. Not sure what to do...amd could not find anything similar.

 

[Eggcessive]

You can take a rubber glove, lubricate a finger, and insert it 1-2 inches inside the vent to feel for an egg. Only if you feel an egg, give a Tums or calcium tablet crushed with food, and place in a warm bath for 30 minutes up to her wings. Also check her for lice and mites under her vent.