I frequently have high readings at the drs, then I go back the next morning and the nurse does it and it's normal. So I would ask to be rechecked, first thing in the morning when you are calm and haven't been racing around and if necessary offer to go back in a fortnight for the same sort of check again.

My dr has always been quite nervous about BP and since I'm quite overweight AND am now 35 yo I think that's the reason as it does predispose. However I wouldn't agree to go on meds after a single high reading, especially not in the circumstance you've just described.