jagged line blocking vision

I recently several strange occurances with my vision. It is hard to
describe, but it is like a jagged line that seems to start in the edge and
moves towards the center over the course of an hour. Its not a solid line,
but seems to blend with what ever I am looking at. This seems to occur
with both eyes, but not usualy at the same time. Times it is impossible to
read. I have notices this occurs under moreso under fatigue times and
sometimes with headaches. After several hours of shut eye, it is gone.

I recently had a retina scan and nothing was found. I asked my doc and he
said to take better care of myself and get more sleep.

Any clues as to what is going on?