I have experienced the spotty, 'watery' vision several times a year for about 3 years now.  Today was the first time it was followed by a bad headache.  The only thing that helped was sleeping.   The first time I experienced the spotty, blurry vision, I thought of my mother who was hypo-glycemic (?).  Whenever she felt bad, she would eat something with sugar in it.  I thought perhaps that was what I was experiencing so I ate a piece of hard candy which did nothing.  Symptoms continued until I ate an apple.  The spotty vision cleared within 4-5 minutes and has worked for me every time I've had this problem.   Now I carry an apply with me in my purse at all times.  Today, the apple again did the trick and cleared my vision.  Unfortunately, the headache followed.