I put 41 eggs in my incubator 24 days ago. Here's the thing, only 20 hatched. Is that ok for first round? That not even 50 percent. And also, the 21 that didn't hatch we cracked open outside to see what happened and 13 of them died during the process, 2 of the died while they were hatching, they cracked and never came out. And 6 didn't have anything at all. What happened?