Wife wonders the same thing, Mark.  I blame it on all the grass, broadleaf and tree pollen and the mold spores always bother me.  Really had it thus far this spring, but hey it is almost summer!

You have a good question and I don't know the answer but there are so many allergens out there I blame it on them...

 It is possible you are allergic to glyphosate or its carriers but I am betting on everything else...  Those allergens I mention have been high to very high about every day this spring...