This has happened to me a few times. The first time I thought I was having a stroke or heart attack. Zig zag lines across my field of vision and something that reminded me of static or lightning. The last one I had started with black spots in my field of vision. Whatever I focused on would be covered by a black spot, and I could only see around the edges. The zig zag lines came afterwards.
I've had migraines as well, but auras and the headaches never come at the same time for me.
Once, just once in my life did the zig-zag lines occur and they did in fact look like a cracked window, spooked me out.
The only time I get headaches is from dehydration and stress combined.
