When you approach her, does she fluff up like in the picture? And growl at you? If so, then that's a full broody hen and she wants to sit a clutch of eggs. Some hens will appear to go broody, then quit, then start again - especially young ones who are still figuring things out.
https://www.bing.com/videos/rivervi...45AFD40B7596EB81FB4445AFD40B7596&&FORM=VRDGAR
A broody hen will spend several days collecting the number of eggs she wants for the nest. She may sit on them for awhile, but mostly she'll be off the nest until she has whatever number she was thinking of. Then she'll hunker down and start incubating. If you place an egg in front of her, she'll roll it underneath her body.
Broodies who are sitting on eggs will only leave the nest once a day, maaaaybe twice, to eat and drink. They will eat very little. It will seem like they're starving themselves. They may not poop every day, but when they do..... prepare yourself for it. It will be a huge stinky mess because she will hold it as long as she can. She's not laying eggs so there's room to stockpile the poop for a few days. The poop in your photos isn't broody poop, but she just may not have figured out what her hormones are doing to her.
I'll bet if you give her some eggs to sit on (laid within the last 4 days), and confine her in a space where the ONLY place to sit down is ON the eggs, she will get the idea and hatch those chicks for you. I have a wooden box open on one end, and I put her in there with bedding and eggs, then put a milk crate on its side in front of that box. I put food and water in the milk crate, then stack a few bricks on top of it so she can't move it away from the box and escape. After 2-3 days, she's fully committed to the nest, OR she's smashed the eggs and convinced you that she wants the heck out of there - either way, you can remove whatever you used to block her in there.
If she's not fluffing up and growling at you when you approach her, then she's likely ill with something. If you think this IS the case, then can you be more specific about her behavior than just "acting strange" or "weird" please?:
How old is she?
Does her breathing sound normal, or is it rattly or wheezing?
Is there any drainage from her nostrils or eyes?
How does her abdomen feel to you?
How does her crop feel?
Is her crop full at night and empty in the morning?
What does her vent look like?
Do you know if she's been laying eggs?
Does she walk normally?
How many other chickens do you have?
Have you brought any new birds into the flock within the last month?
Can you take a video of her behavior? (You'll need to post it to YouTube or similar video site, then paste the link here.)
If you answer most of these questions, I'll tag some of the experts here to help diagnose what's wrong and advise you what to do. But we need more information first, so I don't waste their time. Thanks...
