Big Bang is a fact... But...

Actually I had this question for a long time. Since we all know everything started with the Big Bang how from a single point galaxies end up colliding with each other. Of course taking account the gravities of the celestial bodies, black holes etc help in a galactic billiard which make our universe a very dangerous space. On the other hand the design of the universe puzzles me. Especially since in every day life, we follow the rules of the universe. Math, Physics, chemistry etc. So since the universe is expanding it kinda tells us that distance is a good thing... I won't expand on this... just some food for thought.