I had a confusing dream?

Hi i had a dream last night where i was at a school,not mine, but i know it was a school as i was staring out into a field of people doing p.e. then i saw a cloud falling into the earth and just phasing through it as it hit it. after i went to tell my freind,i don't know who but i know he was a freind,but then meteors just came and hit the earth leaving craters and then i just,i dont know, was somehow instantly outside, it was as if i was never inside. then i was running faster than i ever thought possible,for anything, as i was on the other side of a 1 mile,im guessing, field. i then saw monsters who were human-like emerging from the meteors but the meteors were now metal crate-like things and they became like that in the same way i got outside. then from nowhere i saw and heard a female presenter but in my head and it was as clear as in real life. then after that i was somehow in a city which looked like it was designed by the joker and i remember it being hot and crowded. everyone was in panic and the only 2 people i recognised were my freind and his mum who were going to help me. i somehow knew i was in a dream and the only way for me to wake up was by sleeping so i had to find a safe place from the monsters who were VERY strong and VERY fast but i dont know how i knew but i did. the rest of the dream consisted of me,my freind and his mum trying to get a car and run. dont know where but run. anyway what i want to know is why did i dream this and what did it mean?