Dnasty

I've recently been having brake issues with my 06 cls500 (just changed pads and rotors and am getting an occassional rubbing/scraping noise when stopping) and today after driving quite a distance, I noticed a burning smell.. I really couldn't tell if it was burning oil or gas but definitely had a stronger smell then just burnt rubber. It was coming directly from the driver side tire.. nothing from the passenger side tire. I am wondering if this is somehow connected to this occasional rubbing noise my brakes make, possibly a bad caliper? I did a quick inspection of the brakes and the rotors seemed to look ok ( they are basically new). Maybe the pads are sticking? Or something to do with the e brake (no i did not drive with the e brake on)?