Chicken eggs take 21 days to hatch, if you are hatching on day 19 your incubator is running too hot. Check the temps and try again. Remember, research and research some more...thats the path to success.
I hate to say but your mother is wrong and these eggs are NOT going to hatch. In order for an egg to be fertile it must come from a hen that has mated to a rooster...most store bought eggs are from rooster free production farms. It takes a chicken egg 21 days from start to hatch...at almost/over...
Try to remember that all incubators are going to have hot and cold spots, its just how they work. The best way to check your thermometers to your thermostat for accuracy is to rubber band all the thermometers together and they band them to the yellow box in the lid with your thermostat sensor...
General rule of thumb for most is about 24 hours. I tend to wait up to 48 hours if the hatch is taking its sweet time, they will be fine in that time frame without food/water. I have had some issues with getting anxious and causing shrink wrapping that I then had to fix...not fun.
Unfortunately some incubators just do not cut it these days, but with so many on the market it can be hard to choose. I would stick with what has been proven to work. HovaBator is a great and reliable brand, I would look into the 1602 (with a fan kit) or the newer 2370. Both of these are easy on...
That was a rotten egg, it spoiled and turned into a bacteria bomb. We all know what bombs like to do. Hopefully it didnt get on the other eggs and you were able to clean it up before anything bad happens. Make sure to clean your incubator super well, use dish soap and then some rubbing alcohol...
I am sure it is hard for the forum "regulars" to remember when they were new and did not know everything...
Either way, it is a learning experience and hopefully it works out well for the OP.
Nice. I have worked in the industry for a few years, still not ready to take on that task. Sounds like you are though, keep us updated with lots of pics.
Keep in mind, no matter how much research you have think you have done it is never enough. Building a reliable and functional homemade incubator is a task and a half, best of luck.