100nl - 3bet light, put myself in bad spot

[pwalsh21]

Poker Stars - No Limit Hold'em Cash Game - $0.50/$1 Blinds - 5 Players - (LegoPoker HH Converter)

<font color="black">Hero (SB): $103.10</font>
BB: $71.45
UTG: $68.25
CO: $113.45
BTN: $101.95

<font color="black">Preflop:</font> Hero is dealt K J[img]/images/graemlins/heart.gif[/img] (5 Players)
2 folds, <font color="red">BTN raises to $4.00</font>, <font color="red">Hero raises to $13.00</font>, BB folds, BTN calls $9.00

<font color="black">Flop:</font> ($27) K[img]/images/graemlins/spade.gif[/img] 7[img]/images/graemlins/spade.gif[/img] T (2 Players)
<font color="red">Hero bets $19.50</font>, BTN calls $19.50

<font color="black">Turn:</font> ($66) T[img]/images/graemlins/heart.gif[/img] (2 Players)
Hero checks, <font color="red">BTN bets all-in for $69.45</font>

Villain was 42/28/1, but only over 10 hands. I know it was probably a mistake to 3bet here, especially OOP. The board is pretty draw heavy and he insta-shoved the turn. Without reads and 1/3 of my stack invested, what should I do?