Foot drag happens when you don't pick up your foot properly -- the toes don't lift up and move forward properly, and the toe literally drags, tripping you up. Over time, you'll actually see wear on your shoe, indicating the problem. It's easy to trip on the slightest irregular surface, or on the edge of carpeting, or on a threshhold over a door. What you describe does sound like foot drop.
It can happen in either foot, but generally is consistent in one foot (it doesn't switch from side to side, but can occur in either or both feet.)