2 pair Vs Set, unlucky or bad play

quirkey721

So i was play 10p 20p cash table, i had around £11 pound in the big blind. An aggressive player who was playing alot of pots and bluffing alot rasied to 3 bbs from middle position. the cards were folded around to me so i decided to defend with King 9 of hearts. The flop comes 9 3 5 rainbow. Im thinking my hand is good so i bet Half pot to see where i am and to play back at the aggressive player. He flats my raise so im thinking i have the best hand at this point. The turn came another 3 to which i bet again and he calls. The turn is a King which gives me two pair, I thinkin about how the hands been played and who iplaying agaisnt and i shove. He calls and turn over trip 9s. Did i play this hand wrong and what could i have done to avoid going bust?

ricky1984

Post the hand and it will be easier to give some advice