First, don't panic.
Think about what the updates do. They update the software on your machine, not the user data. Your user files should not be affected by any software update.
The onlt way in which user data can be affected is if you open an existing file in a new ir updated program and then save the file in a new or different format.
The symptoms you describe sound like a new or different default format has been preselected to view and edit your files, which is why they look different. Practically all software has the ability to maintain backwards compatibility with earlier document versions, so with a bit of looking around in the Word settings, you should be able to find the option to set Word back to the default option you prefer to edit your files.
So long as you do not save any files with the same name, this overwriting the old versions, your data should remain safe until you manage to resolve the issue. It is most likely hidden in the settings menu, as an item relating to the default format with which to open and save files.