imho, contact falls into one of three catagories:
incidental
marginal
contact that warrants a foul
sounds to me like the initial contact you've described is either incidental or marginal (it certainly was not contact that warranted a foul). a good official should see the start, development, and finish of the play...THEN decide if you have a foul. the higher the level of play, the more i believe you need to hold your whistle before blowing (or not blowing).
at the NCAA level, John Adams has said if contact initiated by the defender interrupts the rhythm, speed, balance, or quickness (RSBQ) of the offensive player...it IS a foul. your description does not meet that standard.
as for the "questionable contact on the shot", i don't think i have a foul either (at least not as you've described).
mbyron is right - contact is not additive.
i am certainly NOT going to call a foul in the last :10 of a game if the contact is "questionable".
hope that helps...
