You can google 'migraine' to get some idea if that's your problem. People try various things to deal with it, and that info will also turn up a Google search.
Thanks. Is there any way to treat it for the time being? It has since went away, but I am almost positive it will return tomorrow or later tonight as it has repeatedly.
Anytime--anytime--you repeatedly get a one-sided headache over or in the region of one eye, some type of migraine headache is a real possibility.
Of course, you need to see your doctor about this.