Sad to say, I have indeed done the same thing. Came home from church one Sunday and late in the afternoon I was surprised when my son asked for the keys to my car. He said the lights were on. I was surprised because although the car is not old by any means it does have that feature whereby the lights turn themselves off after the engine has been turned off for a few minutes. Couldn't find my keys. Yup, you guessed it. The car had been sitting in the driveway all afternoon running. I am, BTW, 61yo and don't consider myself old.