Does your heart ever skip a beat when you hear a noise?

Oh my goodness! So, I'm paying my bills - just now - and I hear this thump, like a noise I wouldn't generally hear, and I creep out of my office - all stealthy like - with a cat comb as a weapon no less... to find that it was probably just the rain, or the cats, or the floor boards or something - the door is locked and there is noone in the basement. Oh, my gosh!
Anyway, so now my heart is racing - does this ever happen to anyone else?