Recent tourney $10 - 20 players on 2 tables.

1st hand and get dealt KdKh - Two players ahead with 2 x BB and 3 x BB raises - I raised to 8 BB. Got called.

Flop All diamonds A high so was on a draw for nut flush as well as second pair. Player before me raises 8BB so I called other played folded. Nothing on the turn. Player in front raised 6BB so flat called. Nothing on river he raised 4BB. I called and he showed an A.

Question: I hate going all in 1st hand on a tourney but I wish I had, also he was reducing his bets giving me the idea that he was drawing. Was I unlucky - seriously out played or could I have played this differently?