Psychedelic coloured flashing lights.

I get the psychedelic lights sobad it makes me blind for a few hours. The coloures are so brilliant its like a full on New Years Eve fireworks display. It starts off as a tiny black hole in my vision, usually in my left eye, then it widens untill the black turns to the coloures. This lengthens out into a brillient zigzag line that pulsates and flashes. Each zig and each zag is a different unbeliievably beautiful colour but it takes away my vision compleatly, It eventually forms the shape of an eyebrow usually above my left eyes vision then travels sideways and up untill it disappears into my skull. Then, inevitabley the headaches start. Some last a few hours but most a few days.
How many others have this particular aura?