In your video you chose Upload Date under the Sort By heading, meaning YouTube takes what it considers to be the most relevant videos from whatever time period it chooses and sorts them in the order that you request.
There's a separate heading, Upload Date, where you can choose to actually select only videos uploaded in a given period.
As to why you video didn't show up in the original search, I noticed that all the ones that did had many, many more views than yours so that's probably part of the criteria.
It says UPLOAD DATE, there was no other criterion.
Remember last week when you were claiming that the UPLOAD DATE under Sort By somehow factored in what was considered the most relevant videos? Well, at the time I pointed out how absurd that is. Well, apparently YouTube noticed my complaint and NOW when you click UPLOAD DATE under "Sort By" it does accurately reflect the upload date. Case in point: My video I uploaded today about Beto O'Rourke's hair suddenly turning gray. If you Search "Beto O'Rourke" and click UPLOAD DATE under "Sort By" it now accurately shows the upload dates IN ORDER which it didn't do before. My video is now several down from the top. Soon after I uploaded it my video was IMMEDIATELY at the top because it was the most recently uploaded video for a few hours that was uploaded under the search terms "Beto O'Rourke."
So not only have you been PROVED wrong, but my video complaining about it FIXED the problem because YouTube obviously took note and rectified that.
Now go my son and sin some more.