Who made the bigger mistake here?

[KdoubleK]

$10-$20 NL at the commerce, have 900 in front of me and am on par or covered by most of the table except guy 2 to my right who has 155 left. Get dealt Qh10h in the BB. UTG+1 limps, shortstack limps on the button, SB completes, I rap the table. Flop Kh9h3s. SB checks, I check, UTG+1 checks, short stack goes in for 135. SB thinks about it then calls. There is 350 in the pot right now. I figure I can smooth call here but another heart will kill my action. I also consider that SB's call could mean a better flush draw, which would really suck if I hit the turn. I decide to go all in and put SB to the test. To my surprise, UTG+1 almost instantly calls. "Oh crap, I just ran into a set" I'm thinking. Nope, he's the one with the A high flush draw. 5h hits the turn and I'm drawing dead. Who do you think made the bigger mistake and why?