I just went to unplug the coffee machine and there was a bang,the outlet is now scorched.There is also a toaster plugged into the same outlet.Do I need to call an electrician

An Electrician or someone competent to work on Electricity.
Something inside the box is likely damaged, may not be too bad.

I agree, a competent handyman can do this job. The power needs o be killed even if the breaker has popped. The receptacle has broken or most likely one of the wires became disconnected. UIf its just a wire no replacement materials will be needed