Stuck on the flop with two overs

InterPoker Hold'em NL ($0.15/$0.25) $25 max buy-in

I am still getting used to InterPoker, whose NL .15/.25 is much looser than Absolute Poker's NL .10/.25. I don't want to say I was killing AP, but I was profitable and a lot of that had to do with making continuation bets on the flop. Those continuation bets are getting called a lot more on InterPoker.

So I find myself with two overcards on the flop, facing a raise. Your thoughts? CO is 22 VP%IP/6% PFR.

Seat 1: MP2 sits out
Seat 2: MP3 ($5 in chips)
Seat 3: LP ($37.06 in chips)
Seat 4: CO ($70.74 in chips)
Seat 5: BUTTON ($24.35 in chips)
Seat 6: SB ($18.25 in chips)
Seat 7: BB ($7.55 in chips)
Seat 8: UTG sits out
Seat 9: KING ($54.75 in chips)
Seat 10: MP1 ($28.75 in chips)
SB: posts small blind $0.15
BB: posts big blind $0.25
MP3: posts big blind $0.25
----- HOLE CARDS -----
dealt to KING [A[img]/images/graemlins/spade.gif[/img] Q[img]/images/graemlins/spade.gif[/img]]
KING: raises to $1.50
MP1: folds
MP2: folds
MP3: folds
CO: calls $1.50
BUTTON: calls $1.50
SB: folds
BB: folds
----- FLOP ----- [J[img]/images/graemlins/diamond.gif[/img] 9[img]/images/graemlins/heart.gif[/img] 9[img]/images/graemlins/club.gif[/img]]
($5.15 in pot)
KING: bets $3
CO: raises to $6
BUTTON: folds
KING: folds