Why am I hyperventilating!?

Before I say this I want to say that I am not kidding, making this up, nor did I try to make myself do this. So I just watched the Harry Potter and the Deathly Hallows part two trailer for the first time. I started hyperventilating and when the video was over I began laughing uncontrollably. When I saw the first part in theaters last year the same thing pretty much happened. But worse. Basically I want to know why my brain was triggered to start hyperventilating when I saw the trailer. As you can see I'm a pretty devoted fan. When I went to see Pirates in theaters every time a preview came on my heart stopped waiting for it to be hp. Then when it never came on I nearly began to cry. When the man who plays the English king came on I freaked out because he is the actor who plays Uncle Vernon. Its the same deal with hades (Voldy pants) in that Titans vs. Gods movie or whatever its called. :) Oh man I'm such an odd child.