WHAT HAPPENED BEFORE POINT OF SINGULARITY

13.7billion years ago marked the expanding of our universe , but many of us would have generated a question what happened before the point of singularity . Initially it was just a dot in universe which exploded. According to my thoughts what happened before it was there was another universe which was destroyed due to gravitational collapse of every cellestial object and each one attracting the other formed this dot which we call point of singularity it exploded as big bang as the matter and antimatter came in contact with each other we can justify this theoretically by:

Gravitational collapse Universal law of gravitation Newton's 3rd law of motion Action:point of singularity Reaction:big bang