I would post this on the PD forum also, they might know of similar difficult to dx problems, or some there may have had the same dx troubles..
http://neurotalk.psychcentral.com/forum34.html
A sinemet trial may help to see if PD or not.
But the PD members can advise more about that option.
I don't know why the dr would say it is not PD, when it runs in your family history?
Did you ask why he feels it isn't?