I wouldn't worry too much. I've seen them do this for a day or two. It looks like they are just starting to drop down. Shadows appear just before internal pip. Eggs can hatch over a period of 2-3 days even. On your day count... day one is 24 hours after you put them in the incubator. I leave babies in the incubator until they dry and then move them into the brooder. My hands are in and out of the incubator even while other eggs are pipping and zipping.