Ive had the same dream on multiple occasions. It was back a few years ago when i could fall asleep with my lights on and i would just sit criss cross applesauce and read until i read myself asleep every night. (I was 10-11?) So, basically, i would fall asleep, and in my dream i would be in really tall grass and i would be walking/running away from something. As i run away from whatever i was running from, i remember being able to hear something really really loud a couple times, not knowing what it was. Eventually, i would be able to look back and see this huge silver/black ball that would be dropping onto the ground and that was what was making the loud bangs. It would catch up to me as it bounced and rolled closer and closer, until it was about to smash me. I would look up, see blackness fill the "sky" and right before i would get smashed, i wake up with a jerk. Kinda creepy now that i think about it because it happened 10-15 times i would guess. Same sequence, same dream.