Just looking for some feedback

It was my first live tournament. And boy was I nervous. I couldnt believe it but I was actually shaking during the first hand and I didnt even play the first hand. I had heard people say that your first Live tournament can be nerve wracking but I didnt believe them. Well anyway here is my scenario: It was only the second hand of the tournamant. Only the 2 blinds played the first hand so there was really no way to establish any sort of table presence on anyone. We all had $1500 in chips. Anyway, I was the $25 big blind and was dealt A-K of hearts. One limper from mid position and the small blind came into the pot. I raised to $200. The mid position player called the raise and the small blind folded. The Flop came Qh, 3h, 10d. ( I had the Nut flush and the inside straight draw ). I bet $200 and the mid position player raised "All-In". I've already committed $400 of my $1500 starting stack, I have the Nut flush, the inside str8 draw and possibly 2 overcards to his queens ( Thats what i thought he had ) . So i called. He showed Qc-Jc. the turn and river came X and X. and I lost to the Queens. What did I do wrong? Hey, I'm no pro (Far from it) I play casually but I usually can figure out how I played a hand wrong. ( I bet too little, or I bet too much, or I called when I should of raised...etc..) I really could use some advice from some people who know the game better than I do. So please respond. Thank You