I get it a lot and it's getting worse, although I've never fainted. In fact I don't think it's when I stand up too quickly any more, it's every time I stand up if I've been sat down for any length of time.
I've always had low blood pressure, although no one's ever been concerned about it and I have a very low resting heart rate, 36 but I am very fit.
I did go to the GP about the dizzy spells about 2 years ago and he completely dismissed it as nothing to worry about, he even laughed when I asked whether my low heart rate was cause for concern.
Would go go back or is it just one of those things?