Usually, if you open CCC for the next time, you'll find the same settings of the last backup. There you can see from where to where you did the backup.
Other suggestions: If it is just a backup of files, remember a recently changed file that should be on the backup and search for it in Finder or Terminal. A comparison tool like
dupeGuru could assist, too.
If you mixed bootable system clones, did you archiving of changed files (_CCC Archive-folder)?
Edit: What about Console -> CCC.log ?