far to aggressive with this draw?

Paradise Poker No-Limit Hold'em, $0.25 BB (5 handed) internettexasholdem.com

BB ($45.00)
UTG ($37.25)
MP ($31.50)
Hero ($82.25)
SB ($48.00)

Preflop: Hero is Button with 4[img]/images/graemlins/diamond.gif[/img], A[img]/images/graemlins/diamond.gif[/img]. SB posts a blind of $0.25.
<font color="#666666">2 folds</font>, Hero calls $0.50, SB (poster) completes, BB checks.

Flop: ($1.50) 3[img]/images/graemlins/diamond.gif[/img], 5[img]/images/graemlins/diamond.gif[/img], K[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(3 players)</font>
SB checks, BB checks, <font color="#CC3333">Hero bets $1.5</font>, <font color="#CC3333">SB raises to $3</font>, BB folds, <font color="#CC3333">Hero raises to $13.5</font>, SB folds.

Final Pot: $18

I ran the numbers afterwards considering his most likely hand to be Kx
Board: Kh 3d 5d

equity (%) win (%) tie (%)
Hand 1: 46.5256 % 46.16% 00.46% { Ad4d }
Hand 2: 53.4744 % 53.12% 00.46% { AsKs }