Mine start out with a tiny visual disturbance, like if I am reading, I don't see one letter. Then the silver zigzags start in the outer corner of both eyes. The spots get worse for about 20 minutes and then it starts to go away. I also go to a dark spot if possible and lie down or just close my eyes. I had my first one in college during a final exam and most when I am under stress, if not all.
I had one 2 months ago on a first date with a guy and had to leave the restaurant, he thought I am crazy probably but I couldn't stand the light and wanted to go outside and sit in the park where it was dark. I wanted to leave while I could still see clearly. I have had these now for almost 50 years and nothing worse developed. They say smart people get them, lol. As long as you know they go away and they always do. Don't get scared by them.