Falling Upstairs

I write about this, because it still puzzles me. How the hell do you fall....UPSTAIRS!!!!
As Alejandro said "Its like defying gravity." (Well he actually said "dude, thats like defying gravity, thats cool")

So we're in the lockers, the ones smack in the middle of the 3rd floor. Going to my locker, I'm talking(no surprise) to Alejandro and JD. So then Alejandro goes "What's up Natalia, pound it."
Then we see her last 2 fingers are in a bandage. So Alejandro goes "dude, like what happened to your hand???"(Yeah, he's gonna be saying "dude" a lot more in this post.)
She explains that she closed a door on her hand, and I go, what's with you? First you fall down the stairs and mess up your hand, and now you close a door on your fingers, and mess them up too???

This is where the discussion developed. Because I had to be corrected, you see she didnt fall downstairs... She fell UPSTAIRS! Well I said that I could see her tripping up three or more steps, but a whole staircase? As Alejandro stares into space with a blank look on his face, (as usual) I find out that if you jump REALLY high, you can trip upstairs(which I guess involves some Michael Jordanian superjump, and some jetpacks on your feet).

As a tide of midgets in red flows by(the 3rd graders are leaving Mrs. Vallarino's room), we: Mafe, Natalia, Alejandro, and me argue about if you could fall upstairs, and then the conversation is ended by the one force you can't argue with. Mrs. Meadows casually passing by and commenting that we might want to hurry up, or just get a detention(either one...). And Alejandro goes "Dude we better hurry up!!!" (This is the last "dude" you'll hear I promise).

So yeah apparently you can fall upstairs.