Arielle, the worst thing that you can do is worry to much! There is only a small portion of this that is in your hands. You can not control anything but to watch over them and provide them temp an humidity. It sounds as though they are developing perfectly. It should have a dark mass that takes over the egg. Some eill quit developing even in the best of situations, that's just the way that it goes. You stressing will change nothing except for the enjoyment that you could be having now!