I've converted to your CC program about six months ago. Today I opened a folder in Lightroom and tried to edit images made a few weeks ago. I struggled with them and finally realized that they had already been edited. The curious thing is that they had edits that i would never have done, to images I would never had edited in the first place. Can you explain why my files appear tampered with?.
That might be possible while importing those images in Lightroom you have applied a develop preset.
If you want to reset the images , please follow the steps mentioned in the below article:
Select one of the "edited" images in the Library grid, go to the Develop module, and check the History panel to see what changes were made. Any preset used during the import will be listed in the import line.