tough situation against donk who c/min-raised flop a few times

[PleasureGuy69]

guy is 56/23/2. Prior to this, he min raised my c bets 2-3 other times. I felt like I had to take a stand especially IP so I called to see a turn card. I thought his check to me on the turn showed weakness so I bet out.

Should I have bet the river? I think a good range for him would be a pair, 7x, Qx, a flush draw.

Obviously I get no value from a flush draw, and no value from 7x but is the likelihood of him having Qx or a lower pair high enough to make this worth betting?

Full Tilt Poker - No Limit Hold'em Cash Game - $0.25/$0.50 Blinds - 5 Players - (LegoPoker Hand History Converter)

SB: $42.65
BB: $157.85
Hero (UTG): $50.00
CO: $50.50
BTN: $21.35

Preflop: Hero is dealt (5 Players)
<font color="red">Hero raises to $1.75</font>, CO folds, BTN folds, SB folds, BB calls $1.25

Flop: ($3.75) (2 Players)
BB checks, <font color="red">Hero bets $2.50</font>, <font color="red">BB raises to $5.00</font>, Hero calls $2.50

Turn: ($13.75) (2 Players)
BB checks, <font color="red">Hero bets $8.50</font>, BB calls $8.50

River: ($30.75) (2 Players)
BB checks, <font color="red">Hero bets $16.00</font>, <font color="red">BB raises to $40.00</font>, Hero calls all-in for $18.75
Uncalled bet of $5.25 returned to BB

Pot Size: $100.25 ($3 Rake)