Burning tired eyes was one of my symptoms I ignored, telling me to slow it down. When I ignore the tired eyes for too long the body and mental fatigue sets in and is much worse. I do not need or wear glasses as I too thought this may be the problem. I have also found aromatherapy, lavender in particular helpful/ calming (odd, I know) as it is not always possible to take a nap during the day.

I'd like to know any suggestions, too. I get this sometimes and do find that just resting my eyes and closing them for a bit seems to help. Unfortunately life doesn't always allow for this when you're at work or driving the kids around or going where ya need to go.
It sounds simple and obvious enough that you may have already done this, but if not, get your eyes checked and make sure you're not straining them too hard. I wear glasses for work, and can completely see in any situation/condition without them, but on a day where I forget them or sometimes driving at night, the strain, albeit a small one, gets to me.