Could i have played it better, or not?

Party Poker 0.50/1 Hold'em (9 handed) FTR converter on zerodivide.cx

Preflop: Hero is Button with J:diamond:, A:diamond:.
2 folds, MP1 calls, MP2 calls, 1 fold, CO calls, Hero raises, 1 fold, BB calls, MP1 calls, MP2 calls, CO calls.

Flop: (10.50 SB) 6:spade:, 2:diamond:, J:club: (5 players)
BB checks, MP1 checks, MP2 checks, CO checks, Hero bets, BB calls, MP1 calls, MP2 folds, CO calls.

Turn: (7.25 BB) A:heart: (4 players)
BB checks, MP1 checks, CO checks, Hero bets, BB raises, MP1 folds, CO calls, Hero 3-bets, BB calls, CO calls.

River: (16.25 BB) 3:spade: (3 players)
BB checks, CO checks, Hero bets, BB calls, CO calls.

Final Pot: 19.25 BB

Results in white below:
BB has 4h Ac (one pair, aces).
CO has As 9s (one pair, aces).
Hero has Jd Ad (two pair, aces and jacks).
Outcome: Hero wins 19.25 BB.

I don't think you could have played it better. You could have tried cold-calling BB raise on the turn, then see if he leads out betting on the river, giving you an oppurtunity to raise and possibly have the bet capped. But who knows if he would have taken the bait? Good hand.

Well played, sir. ESPECIALLY the turn 3-bet. Chickening out at that point is weak, weak, weak and I love the fact that you 3-bet.

Nope, you bet every chance you got (I'm assuming this is limit) which is what you should do. Nobody raised except on the turn so that was your only chance to reraise. Nice rake!

Standard. Make sure BB and CO go to your buddy list though!