Mine are typically aura only but in the last 6 months I started to get a light headache afterwards. They last 15-20 minutes and I can't read or work on the computer once they start. I have a kaleidoscope zig-zag pattern (in both eyes), that eventually makes a complete circle and then goes away.
They are very common and usually harmless. I remember getting my first one. I was driving from St. Petersburg, FL where I lived to Atlanta, GA to be with my pregnant daughter. It happened while I was driving and scared me deeply.
Since then I have seen an ophthalmologist annually and there is nothing to be concerned about (always check with a specialist if you start these unexpectedly).
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