NL20 - Extracting River Value

[22pajo]

No-Limit Hold'em, $0.10/$0.20

UTG+2 ($3.81)
MP1 ($19.26)
MP2 ($4.10)
MP3 ($14.04)
CO ($28.74)
Button ($19.14)
SB ($4.15)
BB ($21.86) (Hero)
UTG ($4.00)
UTG+1 ($10.93)

Preflop: Hero is BB with J[img]/images/graemlins/spade.gif[/img], 4[img]/images/graemlins/spade.gif[/img]
<font color="#666666">1 folds</font>, UTG+1 calls $0.20, <font color="#666666">6 folds</font>, SB calls $0.10, Hero checks,

Flop: 4[img]/images/graemlins/diamond.gif[/img], K[img]/images/graemlins/spade.gif[/img], Q[img]/images/graemlins/spade.gif[/img] ( $0.6 )
SB checks, <font color="#CC3333">Hero bets $0.60</font>, UTG+1 calls $0.60, SB calls $0.60,

Turn: 7[img]/images/graemlins/spade.gif[/img] ( $2.4 )
SB checks, <font color="#CC3333">Hero bets $1.80</font>, UTG+1 calls $1.80, SB calls $1.80,

River: 9[img]/images/graemlins/diamond.gif[/img] ( $7.8 )
SB checks, Hero ????

<font color="blue"> Obviously its easy say push here but what kind of bets should i be thinking about making here?
are we ever worried someone is playing the A[img]/images/graemlins/spade.gif[/img], for the nut flush, really weakly?</font>