$11: KK on the bubble

Seat 1: Hero (1,770)
Seat 5: irishbum80 (4,440)
Seat 7: Remoc61 (4,720)
Seat 8: pitstop1099 (2,570)
Hero posts the small blind of 100
irishbum80 posts the big blind of 200
The button is in seat #8
*** HOLE CARDS ***
Dealt to Hero [Kd Kc]
Remoc61 raises to 400
pitstop1099 folds
Hero raises to 800
irishbum80 folds
Remoc61 calls 400
*** FLOP *** [3s 5d Ac]

Should I have just pushed preflop?

Now I haven't pushed what should I do?