It's been 21 days and no chicks...still sitting though, do I do anything???

[Farmmama]

Thanks so much to all of you.. OK went out last night to one angry hen who did not want to move. There is "something" in the eggs no movement what I would say is they are "thick and a pocket on one end" - I know all you experienced ones are cringing now with my description but that is the best I can come up with. There were 3 not fertilized so I removed them... any thoughts?