If you’ve seen any of those Keystone Cops movies they look like they are doing at least 85 MPH in those old jalopies. Actually I have some friends who have a nice Model A with a rumble seat and its probably a lot more fun to drive than some of the newer cars, especially on a nice summer day.
It sounds as if machine may have suffered a short or internal problem causing it to go kaput.
I don’t think the machine would have caused you any problems, but perhaps the electrologist getting startled by the machine going “Poof” probably caused the very tiny lesion you describe.
It’s unfortunate, but as they say “stuff happens” or something very similar to that.