KJ reads Q6 immediate reraise as weak....plz share ur thoughts

[HardGrind]

6 handed .10/.25 cash game. I was delt KJ...now I usually wont raise with this hand but considering we were playing short handed, I reasoned that the value of that particular hand increases in this type of circumstance. With that logic in mind I made a small preflop raise from .25 to .55 (nothing outrageously crazy). Everyone Folds to the Button/Villian who calls. Flop comes out 4s Th 6h

I put Villian on at least 1 overcard & figured that my hand was still strong so I made a pot sized continuation bet. The Button IMMEDIATELY RERAISED my potsized bet to double the amount. This struck me as very strange & my initial read was that it was a bluff. I decided to call & tread carefully thereafter.

Here is the hand pre & post flop.

FullTilt Hand History
Seat 1: shaim1312 ($21.85)
Seat 2: HardGrind ($11.30)
Seat 3: Are You Out ($27.90)
Seat 4: MisterBags ($13.75)
Seat 5: n0bLiNx ($16.75)
Seat 6: Cardracer ($7.80)
MisterBags posts the small blind of $0.10
n0bLiNx posts the big blind of $0.25
The button is in seat #3
*** HOLE CARDS ***
Dealt to HardGrind Ks Jh
Cardracer folds
shaim1312 calls $0.25
HardGrind raises to $0.55
Are You Out folds
MisterBags folds
n0bLiNx folds
shaim1312 calls $0.30
*** FLOP *** 4s Th 6H

shaim1312 checks
HardGrind bets $1.45
shaim1312 raises to $3.60
HardGrind has 15 seconds left to act
HardGrind calls $2.15


I will post the rest of play in its entirety after everyones thoughtfull insight on the dynamics of this hand.

Thanks for the read & replies.


Sidenote-Can someone recommend a good hand history converter. I've tried FTR but sometimes it wont read my tourney hands, samething for Lego. Thanks.