KK hand in home tourney--thoughts please

I was in a 8-person, $20 buy-in home tourney last week. It's down to four players (1st and 2nd get paid) and I'm 2nd with T4400. Player to my left is in first with T5000 or so.

I pick up KK in the SB and, when folded over to me (blinds are 100/200), raise to 800. BB reraises me to 1200 (?). I thought I could take the pot right there, so I pushed. Oops--he called, and flipped over A-10s.

You probably know where this is going: an ace hits the flop, I fail to improve and just like that, am playing pool on the other side of the room.

Maybe a better play would have been to call and decide what to do after seeing the ace show up on the flop.

The preflop all-in was a gross overbet--I had gotten accustomed to my raises being respected at the table, and when he re-raised me a meek 400, I think I overreacted by pushing. I am mostly a limit player and rarely play live NL, except in home tourneys like this, so I'm not sure about my play here.

On the other hand, I suspected he had an ace, and thought I could push him out with the all-in, plus earn T1200 without having to sweat out a flop.

Finally, I think I forgot where I was in terms of chip stacks. I could have called his mini-raise, backed off when the ace hit and still had plenty of ammo. But the blinds double every 1/2 hour, and we were 10 minutes away from doubling them to 200/400. I really didn't want to leave those chips on the table.

Anyone play this hand differently, and if so, how? Anyone else push preflop like I did?