I started having migraines when I was about 18 years old. They always started with what I can described best as blind spots in my vision. This lasts for a small hour, but is quite scary. When this aura starts, I cannot go outside. I might mis a car, or bump into people. Reading is completely not possible anymore, letters and words are missing, but they don't seem to be missing (ie. I see the word 'migraines' as 'mies', just the first and last letters).
Usually it after this hour I get a bad headache, but this has faded over the years. I am 47 now and hardly get bad headaches anymore. Still not 100% sure what triggers the migraines/aura's. Usually they happen in the mornings though. Stopping drinking caffeine helped reduce the migraines a lot. Dairy seems to be a trigger, alcohol does not help either. Sugar on an empty stomach also seems a trigger. After 30 years of migraine, it is still a puzzle.
This morning I had an aura at work, after sitting it out for about an hour or so, I though I could continue working. My vision was good again, and had a mild headache. But I discovered that I could not read English anymore, I spend a good 5 minutes on a sentence but could not figure out what the words said. I could read them (like I normally do), but they did not register and I had no idea how to pronounce them. I can imagine that this may scare people when they first get it.
Worst experience was when I was about 25, I got a migraine at work and went home by train. People in the train asked me how I was doing, my face was hanging and I could not talk anymore.
They put me in a taxi to the hospital on the next stop. Even though I knew it was a migraine, I could not explain myself. As soon as I arrived in the A&E I could speak again and I just had a bad headache.