My mouse has a back button so I wonder if the mouse settings or driver is loopy.
https://www.google.com/#q=mouse+left+click+goes+back shows priors but here I don't know what mouse and if you installed a driver, etc.
About 20-30% of the time I click on a link, like button, text box, file or a video (to make it full screen or fix volume, etc.) the browser will go back to the previous page. This occurs with Chrome, Firefox, and even files in folders on my hard drive as well, though less often.
I have run AVG antivirus, Ad-Aware, and Malwarebytes, with nothing substantial detected. Out of an abundance of caution I replaced the mouse. It is really frustrating and difficult to get any work done. Does anyone have any ideas or thoughts? I never had this issue before, and it's driving me nuts.