Chicken not well, sitting still and twitching

[spymeg]

I went out this morning and one of my girls is not well. She came to me and pooped the grapes I gave them last night...almost intact as if she hadn't digested them. She's sitting in the shade and about every 3 seconds her head is twitches like if a fly landed on your head...quick twitch every 3 seconds or so. She didn't eat any scratch or grass while I was out there. Any suggestions as to what to do or should I leave her be if its just a girl thing?

 

[Mutchi]

Sorry about you chicken, I hope some more experienced comes and helps.

 

[spymeg]

Sorry about you chicken, I hope some more experienced comes and helps.

Thank you and me too! I'm in Texas so I hate to think of her not feeling good in this heat!

 

[Mutchi]

Thank you and me too! I'm in Texas so I hate to think of her not feeling good in this heat!

Ya I would hate to be feeling sick in a Texas town, I wouldn't want to be sick in the cold weather here in Montana either!

 

[Goosebaby]

How hot did it get the last few days? She could have heat exhaustion which will cause poor digestion.
Another worry is kidney problems if she hasn’t been drinking enough.

Also how old is she?

What feed is she getting?

What do her droppings look like?

 

[spymeg]

Also, there was poop on her egg last night!! She is 13 months old, layer feed w/oyster shells and droppings are usually normal except today when the grapes came out. They have a huge pool of water along with their waterer and I haven't noticed her not drinking...but I'm not out there all day long. It's been super humid here since we had like 3 months of rain and it could just be too much for her

Temps are high 90's but real feel is probably over 100. They were ok last year in the over 100's but it wasn't this humid.

 

[spymeg]

I just brought another waterer out with some ice cubes and she's still in there drinking!! Probably dehydrated. But she's still twitching her head...

 

[Goosebaby]

The humidity could be a problem, the heat might be just too stressing but also heat + moisture equals the perfect growing conditions for bacteria, mycoplasmas, parasites, and fungi which could all cause her issues, she might even have several issues going on.

Considering how quickly this came on my guess is she’s been sick for a little while and hid her symptoms, of she has heat exhaustion.
It might help her bringing her inside somewhere cooler with some electrolytes in her water and see if she perks up.

 

[Goosebaby]

Also poisoning is another possibility, like swallowing bits of metal.

 

[AnnaWolf]

The twitches can be a sign of heat stress or brain injury, but to be sure more info is needed.
How warm is it?
How many chickens in the flock?
Is she eating and drinking?
Doe she have any injuries?
When posting more answers showed up.
I would follow @goosbaby's advice and keep a clos I on her.