Since any advice could result in liability if the machine kills you, the only right answer in the USA would be to have an electrician test the setup for any problems.
But for me, my own I'd count my lucky stars and add +1 then carry on using the PC.
Bob
Earlier today as I left my computer running in my room my child began to explore my work area. At first I was okay with it but suddenly hear a popping sound there. I turn around to see that my child had taken the smaller end of a USB cord and stuck it into the operating end of a nearby power socket. The buzzing stopped as the breaker tripped, but the end of the cord was charred and burnt. My computer doesn't seem to be showing any signs of damage, but I am afraid to use it. I am using my laptop to type this; would my computer suffer damage? If so, how bad would it be?

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