He and I had the same dream?

[keywee]

I was describing a dream to two male school pals (let's call them "A" and "B") one day.
As I was telling the story, B asked me questions as if he knew about the dream or even had the same dream.

Here's my version:

I was walking down (with a few friends, including A and B) a street in a "dangerous" city/town.
It was night time and the place was pitch black.
We were walking down a path lined with trees on both sides. One of the trees was blue and glowing. The rest could not be seen clearly due to darkness.

My friends and I were walking side by side. I was in the middle but was sort of behind A and B.
They told me how the city was full of dangerous people carrying offensive weapons with them, such as guns, swords, chainsaws.
We did indeed walk past a lot of people with weapons (sitting around, standing, walking aimlessly).

Soon, I was going down a very long escalator with A at a lit building. He was on my left, and B was no longer there.

Suddenly, a man in black came from behind and put a pocket knife or kunai near A's neck, as though to threaten A. A was calm about this.
I ran and jumped (or flew) to the bottom of the escalator and ran (flew) away.

Eventually I arrived (alone) at a very old and small school. I seemed to know the place in the dream. It had only one floor. The walls were white but dirty. Everything was pretty much destroyed inside. The room I went into was almost empty.

Here's B's version of the dream:

He was walking with 7 other people down a pitch black place.
Soon, he walked into an elevator, and noticed 2 of the people had gone missing.
Suddenly, a man came from above the elevator and pulled out a long sword and threatened one of the people (apparently this victim was A, same as in my dream).
And then a man started shooting at the people inside the elevator.
After that, B saw everything rewinding... and then he got woken up by his mum.

B had his dream a day before me, and we didn't share our dreams until after I had mine. It's highly unlikely he made his up because he's not the kind of person who tries too hard to prove his connection with someone.
We don't have many common experiences at all so this makes the linkage between our dreams all the harder to explain.

Does anyone have an idea as to why we had such similar dreams? Like... why the elevator/ escalator? Why the dark places? Why the threatening with a short knife/ long sword (to the same victim)? And, why did two people go missing in his dream and only two people were left in mine?

Am really puzzled.
Your opinions will be very much appreciated!