AXs hits the Ace

[Mangatang]

I'm never quite sure how to play these.

Loose/passive online, 7 handed.

I'm UTG+1 with A /images/graemlins/heart.gif5 /images/graemlins/heart.gif, UTG limps, I limp, MP limps, CO raises, everyone including blinds call. (I think the call here is alright, even in early position, because this table had been very passive. This was the first preflop raise in a while.)

Flop: 7 /images/graemlins/heart.gif3 /images/graemlins/club.gifA /images/graemlins/club.gif, SB and BB check, UTG times out and is disconnected, I bet (I usually check/fold here with Ace no kicker, but the backdoor flush draw pushed me to bet here. I was planning to fold to a raise), MP folds, CO calls, button raises, SB and BB fold, I call (go against my instinct, maybe because there's only 3 players left now?), CO calls too.

Turn: 7 /images/graemlins/spade.gif, checked to button who bets, we both call.

River: 8 /images/graemlins/club.gif, I check, now CO bets, button calls, I fold. (If the river would have been a higher card, I would have called, also the surprise CO bet had a hint of slow-play).
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
CO had KK, button had A2o. I would have split the pot with the button.

What did I do wrong/right?

Thanks

[Ed Miller]

What did I do wrong/right?

You folded on the river. Big error. The CO plays like a rag doll on the flop and turn after raising preflop and then all of a sudden has the nuts on the river? Not likely... that bet is very fishy.

Otherwise, I think you played fine.

[Mike Gallo]

You could have raised the turn to represent the 7, however not sure if that will make a better ace, or any other hand to fold.

I think you played fine except for the river. You should have called.

[kiddo]

There is 15 Big bets in pot on river. You only need to split 1 in 8 or win 1/16 to make the call okay. I would call.

In a game where someone is coldcalling preflop with A2o, and someone else betting out on river with KK like this, you have to call much more then against players that you can put on a hand. They will start to push you around if you dont do that (like they did this time).

[Noodles]

I dont get why you were planning to fold to a raise on the flop.when the button raises it doesnt mean he has A with better kicker he could be betting a draw and trying a free card.
Also think that you could have called the river for just one bet,were you really that sure he had you beaten and what made you think this?