Ive actually had something similar to that, we've had someone try to break in our house before he was armed with a screwdriver which he used to break the lock on out back door. This was like 3 am in the morning and im awake all night, I hear someone in the house and I freaked out and grabed my masamune replica you know with an 74 inch or so blade. Yeah he turned tail an ran. I was like wtf there was actually someone in here. I just thought it was a random noise XD