yes, those little critters are a good sign, they are pods, it is usually a sign of a healthy tank and usually pop up at the end of the cycle.
This will be a good time to do a small water change, 10% should be plenty.
I am happy to hear that the fish appear to be doing better, try to feed them some life brine shrimp a couple of days to get their appetite going.
Avoid overfeeding!!!!!
Good luck!!