It's hard when they cant tell for sure. It was the same for me when DS had chicken pox, thhe GP said she "thinks" thants what it was, and the spots went away on their own in the right amount of time - but they were never noticable itchy like you'e expect with CP, and only 1 or 2 of them ever really looked like CP.

Can you see a different GP for a second opinon?