I know I do - I hate when doctors are non-commital... You "could" up your Vit D. COULD?? Can he just commit and tell you how much?
(Wish there was a way to make a rolling eyes emoticon!)
In any case, you can up it another 1,000-2,000 units and re-test after a week to see if you finally respond.
But I'd call back anyway just to get the actual level. And more importantly, ask him what level he is looking for since he seems to have opinions on what's "low".
Good luck! Everything will turn out fine!!