I totally understand!!
The minute I take the screw out of the machine, it goes into a jar next to the machine. The jar is tall enough so if it's knocked over, it's not going to fall out. I have lost that thing on the floor too many times, spending too much time searching for it under my sewing table. It usually shows itself after about an hour of searching and a few pins stuck in my knees.
Hope you are back to sewing quickly!