babies crying a lot.... what's wrong with them?

I have two WS chicks that are about 3 or 4 weeks old that have been crying almost constantly. They have plenty of food and water, they have a heat source and are in a plastic bin that's covered (not completely so air will circulate) the only other thing is that the hay is a little dirtier than usual because they didn't get to go outside today. It was too cold for them to go out. I have tried holding them and letting them sleep on me and they were quiet for a little while and really really wanted to stay but I really really had to get up.
Last time I did this I had 4 babies and somehow they were quieter and less messy. These two produce more poop and go through more food than the last four combined. What is up with that??
Could it be that the two of them just can't keep each other warm enough? Obviously an excuse to get more
Looks like I'll be making a trip to the feed store tomorrow unless someone tries to stop me. *sigh* go ahead, someone stop me.

 

Quote:They are terrified of anything non-organic looking. If its not hay, feed or water, its a no-go. I even tried putting a towel in with them to help cuddle them and they wouldn't go near it. They're very chicken-ey.

 

Quote:Uh, no, I had a parakeet that screamed at the top of it's lungs half the day. This, nor a crying baby don't even come close to that dang bird. I swear though, one of the chicks just screams for the sake of doing it. She seems to do it in her sleep as well.
I tried putting them with my big girl but she pecked them and made them scream.
They probably hate me at the feed store; I'm the lady that comes in and inspects the chicks thouroughly and tells them is anything looks amiss. They don't like being told their business, lol! So, yeah, I look them over pretty well before making a selection.

 

Their water was dirty! How could I be so blind?? It was dirty on the side that I couldn't see. At least they didn't drink it. I fixed that and all was quiet. Seriously, these babies drink a LOT!

Thanks everyone for the ideas

I'm looking forward to giving them various treats. I suppose egg yolks are a good place to start. I've heard yogurt is a fav but my big girl hates it. Her fav is very warm "chicken mash", which is her regular feed soaked in very warm water. Oatmeal will be next.