25NL block this river with my underpair?

[Genz]

Villain is getting on my nerves. I have the feeling he always calls me in position. He will always peel on the flop and then bet the turn and the river weakly. As far as I can remember, up to that point I never had anything so that I could look her up (think of whiffed AK, JJ on AK board etc). He is running 35/0/2.7. On the turn I pick up a double belly buster and I go for the outs instead of donating money. On the river I feel like I gotta see what he has, because he is playing so weirdly. So I block for a small amount. Reasonable?

Poker Stars - No Limit Hold'em Cash Game - $0.10/$0.25 Blinds - 5 Players - (LegoPoker HH Converter)

SB: $5.15
BB: $25.30
UTG: $25.00
<font color="black">Hero (CO): $45.80</font>
BTN: $14.25

<font color="black">Preflop:</font> Hero is dealt 8[img]/images/graemlins/spade.gif[/img] 8[img]/images/graemlins/club.gif[/img] (5 Players)
UTG folds, <font color="red">Hero raises to $1.00</font>, BTN calls $1.00, 2 folds

<font color="black">Flop:</font> ($2.35) T[img]/images/graemlins/heart.gif[/img] 9[img]/images/graemlins/heart.gif[/img] 6[img]/images/graemlins/club.gif[/img] (2 Players)
<font color="red">Hero bets $2.50</font>, BTN calls $2.50

<font color="black">Turn:</font> ($7.35) Q[img]/images/graemlins/diamond.gif[/img] (2 Players)
Hero checks, <font color="red">BTN bets $1.50</font>, Hero calls $1.50

<font color="black">River:</font> ($10.35) 2[img]/images/graemlins/spade.gif[/img] (2 Players)
<font color="red">Hero bets $3.00</font>