What is a moment that you experienced that was scary, but turned out to be nothing to worry about?

"My moment is a bit silly, but a few years ago I was up late at night when I heard what sounded like keys or a keychain being moved, y'know, very light metal clinking. The way the house is set up, the bedroom I sleep in had the door to the backyard. In reality it was two doors a screen door and then a wooden door. My brother was already asleep and I knew for a fact my parents hadn't gone out and they were asleep as well. I think "Someone's trying to break in" and I grab the bat underneath my bed (I live in a somewhat bad area). As I focus on the noise, I start to pinpoint it coming from somewhere else. It was the AC. "