Hi there it's my first time of hatching chicken eggs I've currently got four chicken eggs in an incubator that are fertilized and growing nicely to what ive seen by candle lighting them I'm now on Day 21 and nothing really as started to happen, no pipping no movement nothing, I know that sometimes eggs can take a little longer then 21day to hatch but how do I know if there okay or not?? Also I've put my ear to the incubator and I think I can hear noises of them tapping but I'm not too sure if it's the incubator motor or the chick. If it's the chicks then how long roughly would it take for them to start pipping or is it just a waiting game? Thank you in advance