50NL, Flopping bottom two pair

[ungar2000]

Villian is 42/19/3.67/48 hands.

I was playing Tag/Lag

Full Tilt Poker
No Limit Holdem Ring game
Blinds: $0.25/$0.50
6 players
Converter

Pre-flop: (6 players) Hero is Button with 5[img]/images/graemlins/spade.gif[/img] 4[img]/images/graemlins/spade.gif[/img]
3 folds, <font color="#cc0000">Hero raises to $1.75</font>, SB folds, BB calls.

Flop: 4[img]/images/graemlins/club.gif[/img] 5[img]/images/graemlins/club.gif[/img] 9[img]/images/graemlins/heart.gif[/img] ($3.75, 2 players)
BB checks, <font color="#cc0000">Hero bets $3</font>, BB calls.

Turn: K[img]/images/graemlins/heart.gif[/img] ($9.75, 2 players)
BB checks, <font color="#cc0000">Hero bets $7</font>, <font color="#cc0000">BB raises to $16</font>.

What do you do when checked to on this turn??
What is your line once he C/R tiny?

thanks