I had some "goofy symptoms" after switching to vaping as well. I felt uncoordinated and sort of clumsy a couple weeks in. Oh, and caffeine (I always drank lots of coffee) seemed to affect me a LOT more. Cutting back on the coffee and drinking plenty of water, the clumsiness just seemed to go away after about a week or so.
And from what I've heard, aren't most reactions to PG are fairly quick to surface? For me, vaping high-VG liquids gives me a "greasy" feeling...