Files won't move to FOLDERS and/or saving in folder WRONG!

I have simple, word documents on my desktop, along with a new empty folder.

I open the folder and try to drag one of the docs to the folder...

It goes into the folder as magically turns into, and saves as a SCREEN SHOT I took last WEEK - that has since been deleted! And, the original doc I tried to move is still on the desktop!

Tried:

• I've rebooted.
• Deleted folders and created new.
• Duplicated and renamed docs.
• And, there are no special permissions or anything on these docs.

I'm using Mojave.

PLEASE HELP! This is the strangest thing I've seen.

Thank you.