I was having these bouts with anxiety and vertigo when I would go out for a walk. I had a hunch that it was anxiety fueled since it wasn't an issue at home..But it became really troubling since I do have PD, and was concerned that my PD had progressed. I am still early stage. Anyway, I was having a sort of a disequilibrium (vertigo?)which has since been ruled out by my P.T.as I have passed all the tests to rule out BPVD (benign paroxysmal vestibular disorder). He encouraged me to practice walking, focusing on a target 20 feet ahead, while blocking out all peripheral stimuli. The ambient stimuli was revving up my anxiety and thus tending to throw off my sense of balance. Now, after working at this for a few weeks, I am (proud to say), able to walk with ease!
So my conclusion and lesson learned: Not all symptoms point to PD!!!!!