My vision went black and white once when I was 11 or 12. I was standing in the sun too long (school had prayer in the morning and then somebody had come to the school to talk about cancer awareness). The school assembly went on longer than usual and It was really hot that day. I began feeling too sweaty. My vision went black and white and I blinked several times in disbelief while trying to fix it. Then I called a teacher and she let me go into the classroom to rest. I rested my head on the desk and shut my eyes till the assembly was over. My vision returned to normal and I broke into a cold sweat. I was back to normal after a while.

I didn't tell my parents because I was embarrassed so I didn't go to a doctor that day.