No! ... the big bang occurred 13.8 billion years ago, and that produced the form of this universe that we can detect today. But the energy potential that produced the big bang, existed before the big bang.
Most likely, that energy potential has always existed, ie it's "eternal" (there's probably no other option). I.e.; the total energy of this universe (inc. any other universes in any multiverse) is probably fixed & constant (in fact, the total energy is actually Zero if you add up all the forces that act in opposing ways, ie attractive vs repulsive) ... all that happens to produce any universe (inc. ours) is that at various moments that eternal energy (a set of various interacting energy fields) changes it's state, to produce what we call a new universe via a process like the big bang.
The reason for that change of state is also fairly well understood, and I've explained it here many times before (you can find it explained in almost any popular level book on the Big Bang or on Multiverse models, such as the Many Worlds book by Alex Vilenkin, or anything from Alan Guth or dozens of others in this field).