Bad Play w/ 66

[Choven]

I'm playing .5/1 NLHE at Crazy Vegas (I took advantage of $10 no deposit bonus, built it to 25 for the buyin, built that to 90, started today's game with 25). I'm in LMP ($73) with 66. The game has been loose PF with almost everyone calling the BB, a few folds on a raise to $2, and few callers on larger raises. So, I call and seven of eight see the flop.

Flop comes 332, two diamonds (I have a diamond)

Checks to guy on my right who bets $2, I call with top pair, everyone else folds. I called mainly with top pair, and backdoor straight and flush. My read on this guy is that he had to high cards, but not an Ace-High since he usually raises PF with these regardless of position.

Turn brings 7d--not the diamond I wanted, but I still feel I have the best hand. He checks, I check.

River brings a 2 giving the board 3's and 2's. Guy to my right has about $140 and bets $103. I thought about calling, but looked at the size of the pot. Before his raise, it was around $10. I asked myself why he would have bet on the flop, checked on turn, and put in a monster raise on the river to win $10. Two things came to mind: 1) he made a flush and slowplayed the turn, or 2) he paired sevens. He could have had Ace high (Ax), but why make such a strong bet? The bet almost screamed at me to call. That is why I folded and he took it down.

Questions:
1) Should I have led out on the flop and/or turn?
2) Should I have called my $70 to win $10 on the river?

BTW, there are three poker sites offering no-deposit bonus. I've played on all three and ready to cash out. The sites where listed in the Internet forum.