$3 Turbo KK Ace flops,facing a small bet

[Turlock]

PokerStars No-Limit Hold'em Tourney, Big Blind is t150 (7 handed)
BB (t1120)
UTG (t1770)
MP1 (t5235)
MP2 (t500)
Hero (t3360)
Button (t865)
SB (t2150)

Preflop: Hero is CO with K[img]/images/graemlins/club.gif[/img], K[img]/images/graemlins/heart.gif[/img].
<font color="#666666">3 folds</font>, <font color="#CC3333">Hero raises to t450</font>, <font color="#666666">1 fold</font>, SB calls t375, <font color="#666666">1 fold</font>.

Flop: (t1050) A[img]/images/graemlins/heart.gif[/img], 4[img]/images/graemlins/spade.gif[/img], T[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">SB bets t300</font>, Hero ???

I hate these situations,am I supposed to just give him credit for an ace?

What pearls of wisdom can you give me for when this happens?