'''++@lanaalexander++'''
you are safe for as long as you keep it unplugged. At this point I would suggest you either take it somewhere for repair or properly dispose of this one and purchase a new one. I would not suggest for you to repair it or even open it. There are a couple of heavy capacitors inside the MW that can carry lethal voltages if touched. So unless you have repaired MWs or are familiar with high voltages, keep it unplugged until repaired.
It will not come on fire while unplugged!