I think you are right to be skeptical. I would be. Perhaps not because of the odd run of PVC, but more-so due to the other unpleasant symptoms you report which are intrusive, worrying, unpleasant, and that affect your sense of security. IOW, I won't go so far as to discount her expertise about the inherent danger of some occasional PVCs, although hearing that kind of comment P's me off because it sounds dismissive, but most MDs know to treat their patients' symptoms seriously.

BTW, your self-description suggests to me an enviable condition in terms of overall health.