School shooter

In this dream, I had just arrived in an unknown town and was at the ticket counter of the train station.  I overheard a man and a woman there talking about a shooter going to the local college to start taking people out at random.  As it happens, that's exactly where I was going.

It turns out everybody knew this was going to take place, but had been prompted to act normal so that the proper authorities could handle the situation by ambushing the shooter.  Anyway, I arrive at the college and wander around a bit.  I later find myself in a toilet, and just as I finish taking a piss, I see a food delivery man enter, and I immediately know this is the shooter.  I hurriedly leave the toilet without even bothering to wash my hands and start running down a winding staircase.  I notice other people rushing around, also alert to the fact that the shooter is now in the building and preparing for his rampage.

The staircase seemed to descend several floors below and I know that if I run all the way down, I won't have time to outrun the gunman, so I jump over the side.  Normally, a drop like this would be fatal, but I manage to float to the ground amidst the chaotic throng of people running for their lives.  I reach a fire exit that's now open and step outside where it is night time all of a sudden.  I am standing on a balcony and look across to see squad cars and police vans preparing their ambush.  Something tells me it's not safe to go this way, so I re-enter the building and look for the entrance.  I eventually find the entrance and head towards it and notice that it is daytime again.