As long as they haven't externally pipped it will be fine to candle--you won't shrink-wrap them. I'd take a look at all of them now to see if there's any movement or internal pips. Just remember that the chicks need a buildup of carbon dioxide in the egg in order to start the convulsions that...
There might be pips on the undersides of the eggs. And sometimes the pips are more like little hairline cracks--almost impossible to see. There's nothing you can do to help them along if they haven't pipped yet. Just sit tight!