hand situation

[gomer]

This ones been bugging me, so I'm posting it here to see what peoples opinions are...

live tournament. about 30 players, mostly decent. blinds 50/100. I am one before the button. Both I and button have about 1800.

I have J10 spades.

1 limper in MP. I limp (right?/wrong?)
Button raises to 300. Blinds pass, MP passes, I call (right?/wrong?)
Flop comes Jxx with one spade. I think 'crap' and then I push in with as much confidence as possible. Is this the wrong move?

This is in a fairly small tournament, so I did figure I needed to make a good sized move at some point, but still wasn't looking to get knocked out (obviously). I had no read on the other player at the time, although in retrospect, she did say 'you called that bet?' when I called pre-flop, indicating (perhaps) that she considered it a big bet.

Button calls with KK and takes me out.