Has she returned to the nest?
Eggs can get a bit chilled and still be okay, so don't give up hope.
As to the hen, if she has access to food and water within reasonable distance, I suggest leaving her alone.
You can definitely interrupt their nesting instinct by taking them off the nest. Usually they resettle in a few hours, but sometimes it is a different location!
Most hens get up once a day to eat, drink, and poo one very large poo. You usually won't see them do it. They also lose quite a bit of weight, and their combs are pale (from hormonal shifts) which is natural. This is part of the brooding process.
If your hen is so weak she cannot move, or is bone thin, then you need to intervene.
But until then, it is best to leave nature alone. Momma knows what she is about. She will get up and eat/drink/poo when she is ready, and will go back to the nest.
Just make sure she can easily get back to the original nest without confusion (which sometimes happens).
LofMc