What Causes Blurred Vision Followed By A Headache?

Very occasionally, over more than 20 years I get blurry vision, mostly only in 1 eye, lasting abt. 20 min. A minor headache will follow, also lasting abt 20-30 min. Yesterday at a dr s office I started in the waiting room with the vision and headache problem. When I was in his office, I could not properly express myself, could not find some of the words right away. I slowly came out of the fog on my way home, having been brought by a driver. Once back in my apt. I seem to be fine. I am 82 yrs old, living in an independent facility. While I had the vision and headache situations over the years (eye drs saw no problem) I did not have the speech impairment, but also never spoke much during those episodes unlike yesterday. Doc charted it as confusion. I had a fall in Dec 2016 resulting in a hematoma on the brain which was cleared, many x-rays and MRIs were taken then. Anything to worry about?