hi me and my boyfriend purchased an incubater off ebay and some eggs we have our own chickens at home but wanted a few more. we turned the eggs 3 times a day and locked them down on day 18 but were on day 23 and still they havent hatched the eggs keeps twitching and have been doing this for around 4 days so their still alive i guess. so last nite my boyfriend like a wally cracked open one of the eggs that havent moved and it was a fully formed chick but was dead so he says altho the yolk sac was still on the outside. anyone with a bit of help would be great is it common for the chicks to go over the 21 day rule??