I'm really nervous. I am hatching my second batch of eggs, and the batch is currently on day 15. I candled just a couple of minutes ago with a decently high powered flash light, and I couldn't see anything! It was all black, no veins or anything. I could see the air cell and that is just about it. My incubator manual has a picture of an egg with what looks like an air cell on both ends of the egg, the rest being black, and says that this is what a late death inside the egg looks like. My eggs don't look like that, after looking for a few minutes, I confirmed that there is only one air cell, and nothing else within sight. Is there something wrong? Am I being overly worried and paranoid or is there actually a problem?