All's well that ends well:
Glad you didn't have to use your shotgun. Probably was someone trying to get in the wrong room. I have even had people actually open my room door (which I didn't close all the way, my fault) and then they apologized, etc.
However, it could just have easily been a bad guy, you just never know nowadays. Best to always be prepared (armed) in your room, just in case.
As you are NOT in your home, you will need to exersise a bit more caution defending yourself, (being in a public place as in a motel, etc.).