How to undo Cleanup pressed by mistake on desktop

Hello

I was wondering if anyone can help me with this. I had quite a bit saved on the desktop. Was going to change the desktop background and by error pressed this button-"clean up my mac" which is just below it. It all of a sudden kind of multiplied all the files on the desktop and the background became full and almost nothing can be seen except with all the files repeating themselves. I restarted the mac but nothing is happening and it still stays the same. On finder in the desktop section each file is single and not duplicated. I have tried to clean up by name etc but nothing is happening. Not sure if anyone has any tricks.

I have MacOS High Sierra