I killed someone in my dream lastnight

Really creepy
I was horseback riding and ran across two men out in a field. they were coming from a concert across the field and they talked a while with me. They had a jar with wires wrapped around the lid threads, when I ask them about it they said it was classified and I left it at that. That's the point when my horse was spooked and ran off without me. I later went and either found another horse or found the original one, but either way I found myself back on a horse. Not long after that I was playing a slot-machine in a casino. The setting was a backroom sorta, I vaguely recall I had some sort of devices, not sure what it was about. Just then there were these same two men in the same room as I was in at the casino. when I talked to them they said I saw the classified device and one man closed the only door to the room. The other man came at me in an offensive move. That's when I pulled my knife out of my pocket, as he approached me I stabbed him twice in the neck, now I really recall the wounds as graphic. He fell over dead and the other guy ran from the room. That's when I woke-up and told myself to not forget this dream/nightmare.

What's it all mean.