I decided to do a test run with my incubator, and tossed in the last 3 eggs we had been given from the man that sold us the quail. He told us that they were fertile, and had not been stored for very long. So I figured what the heck. We are on day 3 now, and I just candled them, and I see that near the point of the egg there is some darkening at the point. Any tips on what I should be looking for?