AA on monotone flop, I swear this isn't a bad beat thread

[fatduck]

Paradise Poker No-Limit Hold'em, $0.25 BB (7 handed)

Hero ($273.50)
BB ($58.50)
UTG ($15.00)
MP1 ($36.00)
MP2 ($38.25)
CO ($55.00)
Button ($37.50)

Preflop: Hero is SB with A[img]/images/graemlins/club.gif[/img], A[img]/images/graemlins/diamond.gif[/img]. Hero posts a blind of $0.25.
UTG folds, MP1 calls $0.50, MP2 calls $0.50, CO folds, Button folds, <font color="CC3333">Hero (poster) raises to $2.25</font>, BB calls $1.75, MP1 calls $1.75, MP2 calls $1.75.

Flop: ($9) Q[img]/images/graemlins/heart.gif[/img], 8[img]/images/graemlins/heart.gif[/img], K[img]/images/graemlins/heart.gif[/img] <font color="blue">(4 players)</font>
<font color="CC3333">Hero bets $6</font>, BB calls $6, MP1 folds, MP2 folds.

Turn: ($21) 7[img]/images/graemlins/club.gif[/img] <font color="blue">(2 players)</font>
<font color="CC3333">Hero bets $10</font>, <font color="CC3333">BB raises to $20</font>, Hero calls $10.

River: ($61) Q[img]/images/graemlins/spade.gif[/img] <font color="blue">(2 players)</font>
Hero checks, <font color="CC3333">BB bets $15</font>, Hero calls $15.

Final Pot: $91

Results in white below: <font color="white">
Hero shows Ac Ad (two pair, aces and queens).
BB shows Jh 5h (flush, king high).
Outcome: BB wins $91. </font>

Before the bad beat police show up, I'm perfectly fine with losing this hand, but I feel my play was just horrible. A big hole in my game is overpairs on scary flops. On one hand a monotone flop seems lucrative because I can make people with naked hearts pay to draw (and at this table I knew they would).

I guess my question is when should I have known he had a made flush? In hindsight I think I should have folded to his raise on the turn.