hand anaylsis - pocket 5s - getting too tricky?

[Keres]

4 Places where I'd appreciate you opinion

Party Poker 2/4 Hold'em (10 handed)

Preflop: Hero is SB with 5[img]/images/graemlins/spade.gif[/img], 5[img]/images/graemlins/club.gif[/img]. CO posts a blind of $2.
UTG folds, UTG+1 calls, UTG+2 folds, MP1 calls, MP2 calls, MP3 folds, CO (poster) checks, <font color="CC3333">Button raises</font>, Hero calls, BB calls, UTG+1 calls, MP1 calls, MP2 calls, CO calls.

Decision #1 Call here? Figure I'm halfway in, there's a few limpers and if I flop a set I'm in position to do some damage.

Flop: (14 SB) 4[img]/images/graemlins/heart.gif[/img], 4[img]/images/graemlins/club.gif[/img], 2[img]/images/graemlins/club.gif[/img] <font color="blue">(7 players)</font>
Hero checks, BB checks, UTG+1 checks, MP1 checks, MP2 checks, CO checks, <font color="CC3333">Button bets</font>, Hero calls, BB calls, UTG+1 folds, MP1 folds, MP2 folds, CO calls.

Decision #2 Is a call here sound? Probably not. Button more than likely has a strong hand, if someone has a 4 I may get popped again. Enough players and bets to make a call here worth while?

Turn: (9 BB) 5[img]/images/graemlins/heart.gif[/img] <font color="blue">(4 players)</font>
Hero checks, BB checks, CO checks, <font color="CC3333">Button bets</font>, Hero calls, BB calls, CO calls.

Decision #3 My ship has come in. Checked on the flop planning on check raising. Button bets and instead of raising I call hoping to get the two additional callers maybe chasing a flush or straight. A reraise I thought would've folded them both and just get one more bet from the button.

River: (13 BB) 8[img]/images/graemlins/heart.gif[/img] <font color="blue">(4 players)</font>
Hero checks, BB checks, CO checks, Button checks.

Decision #4 Disaster. Checked hoping that someone made their flush, had a 4, or that button would bet again. Checked all around. Flush was unlikely - though at 2/4 possible, 4 was possible, and if I thought for a second, would realize that button probably not going to bet with 3 other players in, who'd likely only call if he was beat. So, obvious bet on the river here?

Final Pot: 13 BB

will post results in a followup.