Creepy... :/

So..lets start with the fact that I have no idea how to completely describe this... But try to keep up.
In first grade, I went to a private school and when we excelled, they would give us fake money which we could spend on little things in a "store" they made. One day there was a really cool shark tooth in a bottle that I wanted and I saved up and bought it. When I returned to my desk, my friend Kaitlin said "you have to give that to me because I wanted it first" and at that moment I don't understand what happened. I glanced over and saw a dark figure of a man and everything else around us blurred out. It was just us, about five feet apart face to face. He raised his arm and my hand (holding the tooth I bought) opened and then I gained consciousness and she took it from my hand, which was open and stretched towards her...

So.. What do you think..? I'm not sure what this was or what it means.. But I've experienced many more strange things along the way. I will keep posting.
(I'm thinking of slender man or the operator...but I'm not sure :/)