― David Benioff, City of Thieves
Did I close the door properly? Is Jon really interested in me? Oh shoot! I forgot to send that important mail to the client. My boss is going to kill me. I won't be able to go to the gym tomorrow. I need the extra sleep. Why the hell am I not sleeping??? I shouldn't have had the entire chocolate pastry yesterday. May be Jon thinks I'm fat! Sleep deprivation makes us fat. Damn, I need to sleep!
There's literally no limit to how much your mind can wander when you are desperately trying to get some shut-eye. Going to sleep is okay, but going back to sleep after waking up in the middle of the night can be a Herculean task.