The mental models we humans have made of the world around us, for hundreds of thousands of years until about 100 years ago, only reflect reality at our scale of time, space, mass and energy. A centimeter up to a few kilometers, a split second up to a human life span, a milligram up to a few tons, a few microjoule to a few kilojoule. For us, the Earth is flat, there is no conservation of momentum (because a bouncing super-ball simply jumps up after falling, completely reversing momentum) and no conservation of energy (because all movement eventually comes to a standstill unless there is some propulsion). Masses, obviously, do not attract each other.
Gradually, through machine-assisted measurements, observations and theoretical consolidation we came to the conclusion that these supposedly self-evident tenets do not hold. Specifically, Albert Einstein showed in his 1905 paper Zur Elektrodynamik bewegter Körper that there is no absolute order of points in time. In other words, the implicit concept of a universal time in your question is more than 118 years old. While there is a concept of causality in Relativity Theory, it is strange and I have no qualified idea how spacetime is supposed to behave around the big bang, which is super strange.
And then consider that it would be very surprising if our current knowledge were close to the "bottom of reality"; if all that's left to do was to connect a few loose ends, sweep up the remaining crumbs, close down the physics departments and call it a day.
Among other things, perhaps there wasn't a big bang at all — all kinds of ad-hoc things have to be invented to explain it.
Bottom line: I think it is pointless to do serious philosophy about physics. For example, most non-physicists writing about quantum physics are esoteric loonies. In my layman's opinion, even many physicists do not have a "proper" understanding of fundamental matters (they merely know which formula to apply and are able to do the math, but do not "understand" what it "means"), or there are several of those understandings competing (for example, Einstein, who should really know, was always unhappy about the Copenhagen interpretation of quantum physics). There is really no room for laymen.