Question about my raise on flop with nut straight

[bank]

Do you think I should have raised harder on flop with my nut striaght? Or keep in the flush draw. It was 3 handed so I wasn't sure how much to reraise it or just flat call the guy's raise to 6.

Party Poker Pot-Limit Hold'em, $1 BB (9 handed)

CO ($117.25)
Button ($55.10)
SB ($49)
BB ($50)
UTG ($79)
UTG+1 ($41.80)
MP1 ($19)
Hero ($50)
MP3 ($111.45)

Preflop: Hero is MP2 with J/images/graemlins/diamond.gif, T/images/graemlins/diamond.gif.
UTG calls $1, UTG+1 folds, MP1 folds, Hero calls $1, MP3 calls $1, CO folds, Button calls $1, SB completes, BB checks.

Flop: ($6) A/images/graemlins/club.gif, Q/images/graemlins/spade.gif, K/images/graemlins/club.gif <font color="blue">(6 players)</font>
<font color="CC3333">SB bets $3</font>, BB folds, <font color="CC3333">UTG raises to $6</font>, <font color="CC3333">Hero raises to $9</font>, MP3 folds, Button folds, SB calls $6, UTG calls $3.

Turn: ($33) Q/images/graemlins/heart.gif <font color="blue">(3 players)</font>
SB checks, UTG checks, <font color="CC3333">Hero bets $25</font>, SB folds, UTG calls $25.

River: ($83) 8/images/graemlins/diamond.gif <font color="blue">(2 players)</font>
UTG checks, <font color="CC3333">Hero bets $15 (All-In)</font>, UTG calls $15.

Final Pot: $113
<font color="#990066">Main Pot: $113, between UTG and Hero.</font> &gt; <font color="white">Pot won by Hero ($113).</font>

Results in white below: <font color="white">
UTG shows Ad 3d (two pair, aces and queens).
Hero shows Jd Td (straight, ace high).
Outcome: Hero wins $113. </font>

[greenage]

I’ll take a shot, but I warn you that I’m a newbie.

You take the flop with 5 opponents, the top three cards fall along with an A, K 2-flush. Of the 3 opponents that acted before you, 1 folded and 2 expressed interest by betting/raising. There are 2 more to act behind you.

When the flop action gets to you there is $15 in the pot and its $6 to you. Your stack is $49 (after the $1 blind).

Right so far?

I’ve already got 2 opponents interested in the hand and I’d like to act last for the rest of it so it think a raise is definitely in order.

I’m thinking a flop raise somewhere between half-pot sized and pot size, knowing I’m probably going all-in on the turn. I don’t know how to size it beyond that though.

[tewall]

Re-raise all-in on the flop. With that flop it's very likely you'll get called, and if not you increase your stack by a third, which is fine.