Revived sick chick?

I had a chick that was really lethargic yesterday. She seemed to be puffed up and what many may describe was cocci. I separated her and she was initially distraught but settled into the same "zone" she was in prior. With no progress, I tried giving her sugar water with her taking a little. I tried yogurt with food and she wouldn't take any. I tried scrambled egg and she wouldn't take any. So because it was a holiday I couldn't run to the feed store for any corid (but she is on medicated food), I figured I was going to lose my baby chick. Being that I breastfeed my son, that maybe I could try giving the chick some breast milk. With her already looking so bad, I figured it could t hurt. She woke me up shrieking (cause she's separated from the others). When I went in she looks normal and back to herself. When I put her In with the others she went and joined right in with them feeding and drinking. Yeah! Should I still be worried? Should I still have kept her separated? Should I treat any of them with anything else tomorrow? I put acv In their water and fed them all a little yogurt mash.