I think you played the hand well. As Natedogg pointed out, semibluffing with a flush draw is pretty common. In this case your hand is so strong that I think it's a good idea. I don't really know what to make of UTG's mini re-raise. He could be scared or have monster like top set. either way there is so much money in the pot you might as well increase your equity by giving him one more chance to fold. I can't believe he called his entire stack with pukey pocket sevens.