What would you do if you were trapped in the room?

Toss everything in the room out the window to attract as much attention as possible from people on the street. Chairs, tables, lamps, bottles etc.

I would rearrange the furniture daily until the evil entity possessing the room got bored of me and unlocked the door.

Since going with the latter would probably keep you in the room permanently, my best plan would be to stay strong, wait it out, and try every scenario I can think of to escape.

Like someone else mentioned, as long as you're not constantly being scared, I think I would have an easier time "chilling" in the room and figure out what to do. If not, I must fight for as long as I can... or go loco with style. :D