I have developed a headache on the left back side of my head, which also shows occasional pain flashes along a line from there to the left top of my head. I ve had it for five days now, not much change, though probably a bit better yesterday and today. The pain level is low to moderate. I ve been able to work, and to walk a mile or two without much effect. I had cataract surgery on my right eye the day the headache started, though I noticed the pain before the surgery. Doubt this is related, but not sure.