erratic behavior on MacBook Pro

A bizzare effect has just started to happen on my 4 year old MacBook Pro (OS 10.8.5). With no intervention of my own untitled folders are created on my desktop. When I watch the screen the file menu pops on at irregular intervals. Sometimes a file on the desktop is opened automatically. Once the camera was activated. I have run ClamXav and it found no viruses. Parenthetically, this all started when my wife responded to a request to upgrade the operating system, just a coincidence? I thought that maybe the control key was sticking so I worked it but nothing changed. Am I infected? Any help would be appreciated.

That is totally weird! Is there any chance at all that someone could be on your network? Do you do any file sharing or anything that someone could have written a program to execute just to prank you?