Valuebet(?) on river gets minraised

[daume]

My problem here is if this is even a valuebet on the river after the previous action? I checked the turn because of a possible flushdraw.
Comments on all streets are welcome.

Prima Poker skin
No Limit Holdem Ring game
Blinds: $0.50/$1
6 players
Converter

Stack sizes:
Hero: $173.66 (my image should be TAGish, had no confrontation with villain yet)
UTG+1: $104.97
CO: $89.35 ( VPIP 18/PFR 13/AF 3.1/ WTSD 25)
Button: $93.65
SB: $73.68
BB: $9.40

Pre-flop: (6 players) Hero is UTG with Q[img]/images/graemlins/heart.gif[/img] Q[img]/images/graemlins/diamond.gif[/img]
<font color="#cc0000">Hero raises to $4</font>, UTG+1 folds, CO calls, 2 folds, BB calls.

Flop: 9[img]/images/graemlins/spade.gif[/img] 6[img]/images/graemlins/club.gif[/img] J[img]/images/graemlins/spade.gif[/img] ($12.5, 3 players)
BB checks, <font color="#cc0000">Hero bets $9</font>, CO calls, BB folds.

Turn: 3[img]/images/graemlins/spade.gif[/img] ($30.5, 2 players)
Hero checks, CO checks.

River: 3[img]/images/graemlins/heart.gif[/img] ($30.5, 2 players)
<font color="#cc0000">Hero bets $19</font>, <font color="#cc0000">CO raises to $38</font>, Hero ???.