BBvCO KK 3BP Pair board

In Fast Poker hand.

Poker Stars, $0.25/$0.50 No Limit Hold'em Cash, 9 Players
Poker Tools Powered By Holdem Manager - The Ultimate Poker Software Suite.

BTN: $50 (100 bb)
Hero (SB): $50 (100 bb)
BB: $27.15 (54.3 bb)
UTG+1: $37.63 (75.3 bb)
UTG+2: $235.83 (471.7 bb)
MP1: $51.90 (103.8 bb)
MP2: $48.96 (97.9 bb)
MP3: $24.64 (49.3 bb)
CO: $81.56 (163.1 bb)

Preflop: Hero is SB with K K
5 folds, CO raises to $1.25, BTN folds, Hero raises to $4.50, BB folds, CO calls $3.25

Flop: ($9.50) 6 6 Q (2 players)
Hero bets $5.50, CO raises to $14, Hero raises to $45.50 and is all-in

Villain 12/11 (1k hands)
CO open 19%, Fold to 3bet 43%, 4bet 29%

I think 6x QQ is not his range & shove for protect vs AXhh and some KXhh, suited conectors.
Flop flat is better? I think it not called by worse hand & shut his bluff when I shove.