I think I've seen shadow people, page 1

I just read the article: "Did Ghost Hunter's Prove Shadow People"?

I had chills up my spine as I read the description of shadow people on the board and on Tinwiki. I think I've seen Shadow people last year. The odd thing that caused me to dismiss it was that it was in a brand new building at my college that opened only 4 months prior to that. While I would have suspected haunting in one of the century old buildings on campus that have had rumors of ghosts, I dismissed this since I watched this building being built and was there through most of the construction.

So first I start with a question of whether anyone thinks shadow people can manifest in a brand new location?

Now my experience. This was roughly 14 months ago. I was preparing for my senior recital in the Concert Hall at Drew University. (pictures of the hall can be found on this page)
As you can see, this room is not like many other theatres where ghost stories are common. There are no dark wings (well there are, but they are behind the maple doors on stage and they are usually lit except during performance when light would seep out onto stage).

It was early on the weekend, when 90% of the school body was sleeping in. Faculty never showed up on the weekend. And I knew that the two cleaning people who take care of the building were not there that day. I walked in and the building was mine - just the way I liked it to rehearse and make mistakes without anyone hearing me.

I was dead center on the stage - a point from which you can see every other part of the room. I was rehearsing under a dim light, but it was more than enough. The room reflects light very well due to the light colors.
About an hour into my rehearsal, I heard a crash in the middle orchestra seating about five rows back from the stage and sligtly offset to the left. As I turned to direct my full attention at the sound I saw a dark short misty shadow run towards the right aisle before it dissipated. Two seconds or so later, in my periphery vision I saw a much larger shadow form on the right balcony of the house about ten feet tall. I turned to look at it seemed to fade and decrease in size. This was immediately followed by the upper stage right balcony door opening three inches or so and closing loudly.

I stood on the stage very creeped out. The room was dead silent (it was acoustically designed to be quiet). Immediately my cell phone rang behind me and it was my friend calling me. That got my mind off the strange happenings that just occured and I sat on stage for another 20 minutes without further incident. However as soon as I hung up, I booked out of there as I no longer felt as comfortable in the room as I was.

At the time this happened, the building was very new. The locks to the main concert hall were not yet installed in the stage doors - this changed within a week after my incident - which iritated me because I lost my best rehearsal space. I also want to note that before this happened, I had rehearsed in the room on my own at least two dozen times without any problem. I practiced in there at least another 50 times with other groups and I never had an issue. I even worked for the music department as they were preparing to move to the facility - I would show up while the building was still under construction at 5am before the construction people would arrive so I could sing in the hall before others got there - this was before the seats were even in the theatre. I never had any other experience in the room with the exception of that one time.