but also, someone can explain to me why there is matter floating around in space to be a big bang to begin with, where did it come from? lol,
Evolution and the Big Bang theory are really two separate subjects. For all we know, the Universe could have been created, yet life could have evolved on Earth separate of the influence of a creator.
To answer your question, there are many theories. There's a theory that the point of singularity existed forever until the energy decided to explode. Another one, that I personally prefer to accept, is that time itself only started at the point of the Big Bang. What happened before, God knows. ;)