Swollen crop?

Hello, I am new to this site and fairly new to raising chickens (have had mine for a little over a year now). I walked out to the coop this morning and noticed that one of my chickens was acting funny. I let my chickens free range in the yard and they come to their coop when they need water, food, etc.. Well one of them is just standing by the water bowl, not moving or sitting and she has her eyes closed. She will only open them when she takes some water or hears a noise. she doesn't want to eat or take any sort of treat but she will still drinking water. Everything about her physically seems fine, except when I was stroking the front of her chest I noticed an enlarged balloon like feeling which I am assuming is her crop. I compared it to to the others and hers is definitely swollen. Obviously, being new to having chickens, I am panicking. I read a few things about separating her and with holding food as well as massaging it for her. But I don't know if that is correct or if there is anything else I can do? She doesn't want to walk around interact, eat, or anything! Please help! Thank you so much!