File disappeared from stored location and can't be found through finder/recents

I was working on a really simple file (literally only 3 layers, 30 fps at about 2 minutes long) and was saving, closing, and reopening it pretty regularly over the past few days, but had it disappear from the folder I usually keep it in. I've found other posts like this in the past, but they're pretty outdated/none of the methods seem to work for me. I've only had it for a few days so I didn't have it saved to an external place yet, but seeing as how I pretty much animate hours on end every day I had a lot done 😞 please send advice

In terms of more information, this file has had weird behavior in the past. Right before it was deleted it did the thing where I had to save again to a different location, which I did so I don't think that is it. I was also using an imported video as a reference, (file name being "mv.mp4") and before the session started right before it was closed and the file disappeared, it said there was an error opening "mv 1 2 3 4 5 6 7.mp4" or something like that. I don't know if this could be because I usually keep my imported references (which have match document fps on, meaning I re-import it every session for fps to match) in the file after I close it.

I also had a really weird glitch that I'd never seen before keep happening where every time I drew a stroke in a certain place, it would fill another area black that couldn't be undone, so I would close my file and open from the last save. I'll attach a video of what kept happening below. This isn't a major cause of my concern, but I figured the more information, the better.