Please help

[Nutrock]

Hi. Me again.
Last night we went to the allotment to feed our chickens and noticed one was laying on the floor (legs tucked under her) and the other chickens just walking over her. I got worried but because it was about 7.30 I thought maybe she was getting tired. There was another chicken standing next to her, I knew they wasn't right because they didn't run away when I picked them up. I put her in the nest box so no others could tread on her.
I just went there tonight to feed and water them, expecting them to have passed away but she was still in the nest box, the other had got out and was just standing by the feeder. I had given her some food and there's an egg in the box. Just worried. Please help.
Also our grey fluffy ones are making a sort of sneezing noise. I think they might be trying to crow. We got these chickens from auction and 2 have died suddenly since July. We had 4 chickens in the coop before we got them and they were fine. We feed them layers pellets and mixed corn in an auto feeder and they have 2 auto feeders full of clean water a day.
Here's a little video I took tonight.

We have 21 chickens at the moment, we're just waiting to find out if they're cockerels or hens.

 

[rungirl]

Well, it could be anything, but the most likely is that they need wormed. They act weak and tired when they have worms.

Get some Safeguard goat drench from the farm store and a small syringe (no needle) Measure 1/2 cc for a standard full sized hen, 1/4 cc for a bantam or small chicken. Squirt it down their throat. Repeat in 7-10 days. Withdrawl time is 24 days from date of first dose.

If it is worms, you'll notice improvement within a day or two. They should be wormed regardless, so that's where I would start.

 

[Nutrock]

Thank you rungirl. I'll get some first thing in the morning. I hope that is it and nothing more serious.