grade me on this hand

[SNOWBALL138]

Full tilt poker 9 handed 1/2 game

MP3 limps
I wake up in the cutoff with AKo and raise.
Botton pops me back like lightning indicating that he was using an advance action checkbox of raise any. This tells me that he has a real hand (JJ-AA with AQs) being a slight possibility at the bottom of that range.
MP3 calls two bets
I call because I don't have good position, and because I don't think a raise is going to be for value even against three players. I just ran pokerstove on this hand and it confirmed my belief. Even if I give MP3 any 2, I have 31.76% equity in this pot.

I decide to just see a flop and call.

flop comes A 3 5 rainbow.

MP3 leads at the pot. I had a sense that this was a weak bet. I just call, because I know that I can't get any value from my hand if I'm up against a medium PP. At this point I just want to see a cheap showdown, and/or re-evaluate on the turn.
Button makes it 2 bets. Mp3 calls. I call.
MP3 leads when the turn comes off a five.
I call again.
Button raises. At this point I'm thinking that I could easily be up against aces full or trip fives. However, the pot is large, and I don't know these players that well. I call.
River comes off another five. MP3 checks. I check. Button bets. MP3 checkraises. I fold.

Button turns over AA, and MP3 turns over quads for his rivered one outer.

Here are my afterthoughts. I played the turn like an idiot. On the turn, the best I could realistically hope for was a split againse another big ace if the case ace came off.

Also, I think I should have raised the flop. This lets me:
1. define my hand against both players
2. Gives mp3 a bad price if button re-raises and mp3 is pushing a draw.

All and all, I give myself a C+ on this hand.
Anyone else have any thoughts?

P.S. Yes, I know that full tilt poker sucks. I was clearing $.90 of my bonus to unlock my next $20 increment. I don't have any plans to play at that site ever again.