I get this. It used to be a whole lot when I was a little kid, but now it's quite rare. However, I do suffer a lot of tension/migraine headaches. I get them every few days and sometimes every day for a whole week or more. The doctors can't help, of course. Mine tends to look like the one in the picture as far as overall shape, but not the colours and pattern. It's actually in black and white and the pattern can run in a way similar to those rotating barber's signs like the one below, but in a shape more similar to the one in the above picture. It will also progress around my field of vision. It can and has forced me to pull over to the side while driving, but it was only once or twice. Here's the Wikipedia article on it. Does anyone else here get this? Please don't feel under pressure to publically share something personal like this.