Have you ever become filled with anxiety because you knew you were running out of something?
Maybe your battery power on your phone was low during an awesome concert, and you didn't have any way to charge your phone so you could take pictures of your favorite entertainer. Or have you ever been low on bread, eggs, or milk, knowing that funds wouldn't be coming in for another couple of weeks? Or maybe you have a deadline for a certain type of work you have been hired to do, and you are running out of time to complete it?
It seems that we are always running out of something and running somewhere...
