This is our first batch of chicken. I have very little experience with them at all. Any advice is appreciated. 3 wk old pullet. Doing fine this morning, but a few hours ago started acting "weird". Very droopy, lethargic, eyes closed, quiet, not eating, not drinking, and seems to have trouble breathing. She's taking deep breaths, and breathing faster than the others. No one else looks sick. They've not been vaccinated. Any ideas? I honestly don't think she'll make it through the night, but I'd like to try to save her.