When you are sitting around the office, all relaxed and about finished after a hard days work, the last thing you want is to smell some funny odor or buzzing from a nearby outlet. First, you should immediately TURN OFF the breaker. Second, unplug anything from the outlet. Third, all a licensed electrician. It might be more than the outlet that needs to be evaluated.
If you see sparks or black smoke smudge from an outlet with an appliance plugged in, also call a licensed electrician.
If you go to the breaker panel and it has an odd odor, call a licensed electrician right away. Many electrical companies such as Guild member Electrical Solutions of Oklahoma at 405-794-0200 have a 24/7 emergency service just for that kind of a problem.