The Letters Are Crawling Off My Screen

I made a fool of myself and thoroughly confused some coworkers at the Christmas lunch today - I was pointing out a bottle of oil, or similar, which had lots of dark droplets crawling up and down inside, and wondering why they couldn't see it. And trying to work out why the drops were moving - oil and water repelling each other? Heat?

Turns out that I'm hallucinating.

 Text has been moving for me all day - it's really weird. But this morning, it was just around the edges of my vision, now I can stare straight at the screen and watch every other letter in each word floating up and down. If I put my nos eup close, they stand still. But if I'm more than about an arm's length away (or it's really tiny), the text or the dots on the wall, or whatever else, all crawl about.
I think it's a visual aura - possibly Autokinesis. Which is basically the illusory movement of things that aren't actually moving, and a sign of impending migraines. And ...wow. The little dots over the eyes are dancing around and around and tumbling down...

It's caused by spasming blood vessels in the brain, causing bloodflow changes in the region and, hence, visual weirdities. Consistently, it only appears when focussing on small things. It's probably brought on by the all-nighter staring at the computer screen, doing an assignment. I figured it was just my lazy eye being tired this morning... maybe I should have taken the headache as a warning. But then, I don't usually get migraines (I did have one once when I was ten - we were sitting on the floor singing Edelwiess, and suddenly I couldn't read the beginning of each sentence, my eyes just couldn't see that side. And I asked the teacher if something was wrong with the projector and she sent me to sickbay - I couldn't figure out why, until later when it got worse!)