Darkness Beyond Time

I went to swimming pool with my 3 friends. The pool was very strange, it had 2 floors and on some parts looked like waterfall. There where edges on pool where people were sitting. I was sitting there with my 2 friends other one was in pool, swimming. Then, suddenly we heard an evacuation alarm. We all started running, when I got to main hall I noticed it looked like my school, but exit 1 was normal and exit 2 was leading to supermarket in my town. I took exit 2. When I got outside everything was shaking, people were screaming and running. I started running too. Near a police station I stopped by some girl and said her that everything is gonna be okay. Situation got really apocalyptic, I saw that all buildings have leaned towards street like they are near to brake. While I was running among all these people in front of me I saw a car parked on center of street and there was one guy holding a gun. He started shooting at people, he shoot a woman next to me and her blood was all over me, he eventually shoot 5-6 more people that were running and I managed too hide. I spawned a p90 in my hands and decided to go out and kill him, but I didn't.