Depends largely on your temperature. You should be seeing pips and hear peeping now, but don't get overly excited. It can be day 21 or 22 before anything happens too.
One of mine is also day 20. No peeping here yet. I'm terrible, though, I candled last night and saw lots of wiggling.
I'll wait with you
Mine is a barred rock hen and white frizzle bantam roo mix. VERY special to me. I have another of the same on day 19. I also just had a wyandotte hatch perfectly on day 23
I will not open my bator after day 18 unless to add water. Interesting the way you candled from the end. From the video, I couldn't tell if they were good or not. I place my eggs flat on a box with a hole and shine the light up from the bottom through the side of the egg. I thought that all I saw was an embryo in there not nearly developed for day 17 or 18, but I COULD VERY WELL BE WRONG. I am not a pro, but I tossed 11 eggs that weren't solid black in the middle.