Vision Looks Like Kaleidoscope Is It Normal To Go 'blind' For A Few Seconds?

Is it normal to go 'blind' for a few seconds? - vision looks like kaleidoscope

I do not remember when it started, but I know what has happened for years. I know I have on for .. have been well .. before the start of school.

Sometimes when I sit or for some time together, barely moving except my hands for printing or typographical errors, or research at a time, on board computer screen. Then get up, only to be there, and the break.

Why? I do not know, my body is not moving for a while and then I look out into space. But what should I do? I have no idea. Suddenly everything went black and I would have to wait for at-risk anything. He had taken a back by the color change, unless the color is also a time of return does not appear suddenly, but "disappears" from the top down like a wave.

This is not a common thing, a "happens from time to time"


... And then one day my eyes for a few minutes, it was funny, it was like looking through a kaleidoscope. Picture was not entirely clear, but it was like cracks in the form of hexagons, or something like that in my opinion - that the effect on the photo shop.
And then my vision was black and white, and then everything was orange-brown. Then it went black. Then everything is back to normal gradually.
"It used to be.

.... It seems normal .. Right?
- Anyone else go through this?