The question of “What was before God” is interesting – although; the answer must be “Nothing”.
Whether god is, as to some, the atoms and molecules that make up existence, or god is the personal creator described in the Judeo-Christian doctrines. There is an old Latin saying that says “Ex nihilo nihil fit” which means roughly – if there was ever a time that there was nothing – there would still be nothing today (i.e. out of nothing, nothing comes).
The idea of God is that God is that which there is no greater. So if there is something before what we call god, then what we call god is not god, and its predecessor is in fact God (an adaptive form of the argument from ontology by Anselm of Canterbury).
Additionally there can’t be an infinite regress of causes (that is – there has to be a first cause) – and that first cause is what we call God (from Aquinas’ Quinque viae).
In my science courses at the University, I am always amazed, and delighted to see how discussions of science and humanity inevitably come back to discussions on God!