Nightmare naptime

Starting on Friday, Cole has been freaking out at nap time. He starts crying "no nap, no nap" and then when you leave his room he screams and hits the door for up to two hours. Now we go in there every 10 minutes or so to calm him down but he went from 3 hours naps with no problem to a sudden meltdown. We approached nap time a little differently today. First we took down his bug night lights because he kept pointing at them and saying "no bug, bad bug". Then we tried our normal routine which of course failed. So the next step was to leave his door open. I told him that it was nap time and he needed to get on his bed. I also told him that I would leave the door open but he could not come out of his room. I stayed on the couch where I could keep and eye on him and it took about 30 minutes but he finally fell asleep. He looked at some books before making an alligator bed and passing out. He was super quite the entire time so I was surprised when I peeked in and found him asleep. I closed the door so we could watch a movie and about an hour and a half later he woke up crying "open door, open door". Poor guy. The only other thing we can think of that may of had an effect on him was that his current favorite movie is Monster's Inc. And basically that movie revolves around monsters, bedtime, closed doors, and scaring kids. So "Monsters" as Cole calls it, has been shelved right next to Ghostbusters. Lets hope we can get back on track with nap times this week.