this is my first time at hatching anything so i am new at this. I made a homemade incubator out of a 1.7cu ft ref/cooler. it has a fan and two incandesent lights in it, the temp is around 99.5-100.4 and it is a manual turn. I am on day 12 and i just candled the eggs and the top 2/3 of the egg is dark and the bottom pointy end is clear. Is this ok and normal.