Weird hatching egg

I have had a broody that took some eggs to lay on. When one hatched it got cold and I brought it in and decided to go ahead and bring in the other eggs to hatch in the incubator in case some more hatched and got out from under her. The thing is these eggs are not necessarily going to hatch all at the same time since they could have been layed at different times. Now, they have been in my incubator for a couple of days and after some further development I have candled them. This is where I am perplexed. I have incubated before and never seen this. To explain, normally an egg that is further along in development looks like it is more than halfway black with the chick and then the air sac area at the top. Some veins are seen but everything visible looks like it is pressed up against the egg wall.
These silkie eggs have started to look like they are black at the bottom of the egg but then when you get to the middle of the egg it looks like they are not pressed up against the egg wall. It looks like they are in the center of the egg. And so I see light all around and then a murky dark shadow. AND this shadow is pumping. It makes me think they are breathing super fast and hard. Normally I see the veins move and a bump of darkness jerk from the light but these are just pumping right away, not in reaction to the light as far as I can tell.

I have other eggs in there and they are not like this so it has to be just these silkie eggs. I would have thought that it was because they had been outside and then brought in but I have done that too and never had a problem. I was curious if anyone knows what this is or have experienced it. I am going to wait it out and see what happens but just wanted to know opinions. Thanks. and sorry it was so long. I just hope I explained it correctly. It's kinda hard to explain what I am seeing.