Hen Wheezing [please help :( ]

[Simmons Homestead]

It's been a while since I've posted here but here goes:
Today (just a few minutes ago) I noticed one of my hens open-mouthed breathing. I can hear her wheezing (slightly) and she can't cluck like she used to. Otherwise ravenous appetite as usual but she doesn't seem to want to drink water. She still does make sounds though and there's no discharge. Is this an illness or is it something caught? I massaged her throat for a little bit and that seemed to help her. I don't know what to do or where even to start with her. Any advice would be appreciated.
Edit: it sounds kind of like she has a dry throat and it's very subtle but I noticed it instantly because I go out there every day to spend time with them. It wasn't there yesterday as far as I know.

 

[Tookie]

@azygous @Wyorp Rock @Eggcessive

 

[Eggcessive]

Do you have a picture of your hen? How old is she, and does she lay eggs.p? Have you wormed her recently? You can try adding some water to a small amount of her feed and see if she will take it. Feel of her crop, and let us know if it is empty, full, hard, doughy, or puffy/soft. Then recheck her crop in early morning before she has eaten or drunk anything. Also check her lower belly just under her vent to see if it is enlarged with fluid. Have you seen a lot of dust or any mold in your coop? Is there good air ventilation?