NL25 KK Facing Overbet Flop Push

[Suaimhnea]

I forgot to post this hand from a while back.

This was in my first 15 hands at this table. I have no reads on the villians, although he seems pretty loose and has continued at pretty much every flop he's seen.

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

Hero ($18.80)
BB ($45.75)
UTG ($24.80)
MP ($21.05)
Button ($11.40)

Preflop: Hero is SB with K[img]/images/graemlins/club.gif[/img], K[img]/images/graemlins/heart.gif[/img].
<font color="#666666">1 fold</font>, <font color="#CC3333">MP raises to $0.5</font>, <font color="#666666">1 fold</font>, <font color="#CC3333">Hero raises to $2</font>, <font color="#666666">1 fold</font>, MP calls $1.50.

Flop: ($4.25) 8[img]/images/graemlins/club.gif[/img], J[img]/images/graemlins/club.gif[/img], 6[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero bets $2.25</font>, <font color="#CC3333">MP raises to $19.05</font>, Hero ??

I know the flop bet needs to be more--$3.50 to $4.00 would have been better. But as played, is this a standard call?

Any other thoughts on my play would be helpful as well.