I have a hovabator, my first hatch nothing happened, I waited until day 25 then opened the eggs, they were fully formed chicks but hadn't pipped inside. My temp had been a constant 100. I was heart broken but tried again with the temp at 103, every one hatched! Now on 3rd hatch and 7 developing well, today is day 15 so hopefully will have babies early next week. Don't give up trying and don't beat yourself up if this hatch doesn't go well.