Betting with the strongest hand (which you did until the river) can hardly ever be classified as a "mistake", but I believe I would have played the flop differently:
When you flop a strong hand, but not a monster, in early position into a field with many players (I guess there were at least five seeing the flop?), you may want to consider checking. This is not with the intention of slowplaying, but with the intention of someone in later position else betting, so you can checkraise. The optimum is for the person in last position to bet, so you can checkraise and drive out all the stragglers between the two of you. In this particular case, that might not have helped since the SB would still be in, but you want to get rid of people holding, for instance, A9 so that they don't catch a higher two pair, or someone who would otherwise get correct odds
to draw to an inside straight.
On the turn, bet away. You've already declared strength, and you're hardly going to be able to pull another checkraise anyway. If the donk with Q2 actually called a bet and a raise after the flop, you're pretty much screwed at this point, because he might well decide to see the river as well.
Anyway, it's the flop I would have played differently first and foremost. Raising in the BB pre-flop typically doesn't drive anyone out (unless you're re-raised by another early position limper, which you REALLY don't want with your relatively weak kicker).
I would also have bet the river. Mr. AQ would have called with a worse hand. In this particular case, you got hit by a donk, and there's no protection against that, I'm afraid.
But, chances are that had you played it like I would have, you'd have accomplished nothing more than being down yet another small bet, with the way the hand turned out. Food for thought, anyway.