I'm lost with mid sized pocket pairs !

[DickieBets]

I lose alot in this situation :

UTG is 17/15/13 - has folded a couple of times to my 3-bets.

I just don't know what to do here ?

Poker Stars, $0.25/$0.50 NL Hold'em Cash Game, 5 Players
LegoPoker Hand History Converter

UTG: $73.90
Hero (CO): $66
BTN: $31.60
SB: $20.35
BB: $19.50

Pre-Flop: 9[img]/images/graemlins/heart.gif[/img] 9[img]/images/graemlins/diamond.gif[/img] dealt to Hero (CO)
<font color="red">UTG raises to $2</font>, Hero calls $2, 3 folds

Flop: ($4.75) 4[img]/images/graemlins/spade.gif[/img] 5[img]/images/graemlins/heart.gif[/img] 6[img]/images/graemlins/heart.gif[/img] (2 Players)
<font color="red">UTG bets $3.50</font>, <font color="red">Hero ???[/color