Should I call this first river bet?

[milesdyson]

Paradise Poker 0.10/0.20 Hold'em (8 handed)

Preflop: Hero is MP1 with 4[img]/images/graemlins/diamond.gif[/img], 4[img]/images/graemlins/heart.gif[/img].
UTG folds, UTG+1 calls, Hero calls, MP2 calls, CO folds, Button calls, SB completes, BB checks.

Flop: (6 SB) 5[img]/images/graemlins/diamond.gif[/img], 2[img]/images/graemlins/club.gif[/img], 3[img]/images/graemlins/club.gif[/img] <font color="blue">(6 players)</font>
SB checks, BB checks, <font color="CC3333">UTG+1 bets</font>, Hero calls, MP2 calls, <font color="CC3333">Button raises</font>, SB folds, BB calls, <font color="CC3333">UTG+1 3-bets</font>, Hero calls, MP2 folds, Button calls, BB calls.

If you're confused about my play here... The first call is to prevent them having to call two cold. The second call is because the pot's giving ~4:1.

Turn: (9.50 BB) K[img]/images/graemlins/heart.gif[/img] <font color="blue">(4 players)</font>
BB checks, UTG+1 checks, Hero checks, Button checks.

River: (9.50 BB) 4[img]/images/graemlins/spade.gif[/img] <font color="blue">(4 players)</font>
BB checks, <font color="CC3333">UTG+1 bets</font>, Hero calls, <font color="CC3333">Button raises</font>, BB folds, <font color="CC3333">UTG+1 3-bets</font>, Hero folds, <font color="CC3333">Button caps</font>, UTG+1 calls.

Final Pot: 18.50 BB