Bet Again on the End?

I'm in a 20-40 Hold'em side game at a tournament, and I do not know any of the other players.


I get Ad Qc on button. Everyone folds to me, I raise, and only SB calls.


Flop is Ah 10s 3c (rainbow). SB checks and I bet. SB calls.


Turn is 7d. SB checks and I bet. SB calls.


Now I'm a little worried - I figure that if he's calling with a decent made hand, then I can only beat AJ.


River is 5d. SB checks and I bet again. SB calls, shows AK, and takes the pot.


Should I have bet on the River? Also, is it agreed that my Turn bet was obviously correct?

You played correctly. When your opponent does nothing but check and call you should assume your top pair, excellent kicker is good and play it accordingly. Against normal people, you will find they frequently have a weaker ace. Your opponent should have reraised you preflop with slick. Slick is reasonable 3-bet hand anyway and it becomes golden when facing a potential button steal-raiser.