$30+$3, KK, Lvl 1, Is folding gross?

[jaydreb]

This is the second or third hand of the tourney. No read on Villain. Raising the flop seemed standard, but when I get 3-bet it's either push or fold. Is a fold terrible? Should I be flat-calling the donk bet, or raising less if I intend to fold to a 3-bet?

PokerStars $30+$3 No-Limit Hold'em Tourney, Big Blind is t20 (9 handed) Poker Stars Converter Tool from FlopTurnRiver.com (Format: 2+2 Forums)

MP2 (t1500)
MP3 (t1520)
CO (t1680)
Button (t1360)
SB (t1440)
BB (t1500)
Hero (t1500)
UTG+1 (t1500)
MP1 (t1500)

Preflop: Hero is UTG with K[img]/images/graemlins/club.gif[/img], K[img]/images/graemlins/diamond.gif[/img].
<font color="#CC3333">Hero raises to t80</font>, <font color="#666666">6 folds</font>, SB calls t70, <font color="#666666">1 fold</font>.

Flop: (t180) 3[img]/images/graemlins/heart.gif[/img], 9[img]/images/graemlins/heart.gif[/img], 8[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">SB bets t100</font>, <font color="#CC3333">Hero raises to t400</font>, <font color="#CC3333">SB raises to t1360</font>, Hero ???