Need a checkup, KK on sort of ugly flop

[WutRUTryin2Hit]

I find myself in this spot a lot, and I just want a checkup on whether I have a major hole here:

PokerStars No-Limit Hold'em, $1.00 BB (9 handed) Hand History Converter Tool from FlopTurnRiver.com (Format: 2+2 Forums)

saw flop|<font color="#C00000">saw showdown</font>

<font color="#C00000">Hero ($100)</font>
MP3 ($76.55)
CO ($69.70)
Button ($59.50)
SB ($44.10)
BB ($102)
UTG ($89)
<font color="#C00000">UTG+1 ($142.20)</font>
MP1 ($20.25)

Preflop: Hero is MP2 with K[img]/images/graemlins/diamond.gif[/img], K[img]/images/graemlins/club.gif[/img].
<font color="#666666">1 fold</font>, <font color="#CC3333">UTG+1 raises to $4</font>, <font color="#666666">1 fold</font>, <font color="#CC3333">Hero raises to $17</font>, <font color="#666666">5 folds</font>, UTG+1 calls $13.

Flop: ($35.50) 9[img]/images/graemlins/club.gif[/img], J[img]/images/graemlins/club.gif[/img], 8[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(2 players)</font>
UTG+1 checks, <font color="#CC3333">Hero bets $26</font>, <font color="#CC3333">UTG+1 raises to $115.5</font>,

So I have about $50 left here, what should I do here? I have no reads on this villain, but I've been in similar situations a fair bit lately, so just imagine the villian is the average stars .5-1NL player maybe.