50NL: Flopped set, but board is straightening w/ resistance

[bulldog999]

PokerStars No-Limit Hold'em, $0.50 BB (8 handed) Hand History Converter Tool from FlopTurnRiver.com (Format: 2+2 Forums)

UTG ($51.45)
UTG+1 ($50.15)
MP1 ($78.30)
MP2 ($50)
CO ($50)
Button ($35.50)
bulldog999 ($49.50)
BB ($52.55)

Preflop: bulldog999 is SB with 5[img]/images/graemlins/diamond.gif[/img], 5[img]/images/graemlins/club.gif[/img]. MP2 posts a blind of $0.75. CO posts a blind of $0.50.
<font color="#666666">1 fold</font>, UTG+1 calls $0.50, <font color="#666666">1 fold</font>, MP2 (poster) checks, CO (poster) checks, Button calls $0.50, bulldog999 completes, BB checks.

Flop: ($3.25) 5[img]/images/graemlins/spade.gif[/img], 6[img]/images/graemlins/spade.gif[/img], 3[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(6 players)</font>
<font color="#CC3333">bulldog999 bets $2</font>, BB folds, UTG+1 calls $2, MP2 folds, CO folds, Button folds.

Turn: ($7.25) 2[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">bulldog999 bets $8</font>, <font color="#CC3333">UTG+1 raises to $16</font>, bulldog999 ???

Are you raising, shoving, or calling here? If call, what happens if spade comes and villain bets into you?