$50nl - Small Pair Against Retard Bets?

PokerStars No-Limit Hold'em, $0.50 BB (5 handed) Poker-Stars Converter Tool from FlopTurnRiver.com (Format: FlopTurnRiver)

SB ($114.40)
BB ($62.55)
UTG ($50.65)
Hero ($53.15)
Button ($157.45)

Preflop: Hero is MP with 6http://www.flopturnriver.com/phpBB2/...miles/club.gif, 6http://www.flopturnriver.com/phpBB2/...iles/heart.gif.
UTG raises to $2, Hero calls $2, 3 folds.

Flop: ($4.75) 2http://www.flopturnriver.com/phpBB2/...es/diamond.gif, 7http://www.flopturnriver.com/phpBB2/...iles/spade.gif, 3http://www.flopturnriver.com/phpBB2/...iles/heart.gif (2 players)
UTG bets $1.5, Hero raises to $5, UTG calls $3.50.

Turn: ($14.75) 8http://www.flopturnriver.com/phpBB2/...iles/spade.gif (2 players)
UTG bets $3, Hero calls $3.

River: ($20.75) 9http://www.flopturnriver.com/phpBB2/...iles/heart.gif (2 players)
UTG bets $4, Hero calls $4.

Final Pot: $28.75

The flop seemed standard but I feel like I'm getting such a good price on the turn/river that I can't fold.

I don't play it any different 'cept raising river hard when I'm on tilt.

I think a river raise might be > call, no idea where to start on the numbers though.