Supernatural occurance?

On Friday I had such a strange experience. It happened in a few seconds but it was a bit frightening.

Coming back from the art walk that was held downtown, Stephanie and I came back to our room to relax since we had been walking for nearly four hours enjoying the shops, and art galleries. I sat down at my desk to get off my feet when all of a sudden it felt like a hand was placed on my right shoulder. The feeling melted through, and the muscle that was touched burned for a brief moment. Though when I felt the touch I jumped out of my chair startling Stephanie in the process.

It was strange, there aren't any rumors of Cowden Hall having ghosts haunting the building. Stephanie joked that a ghost followed me from downtown or on some part of campus. But whatever it was it really did startle me. I don't feel scared being in my room alone or anything but ever since that I've been having troubles falling asleep for some odd reason.

Maybe my self-conscious being alert?