Gotcha! Is that what you thought? Did you really think you had posed the ultimate unanswerable objection to the existence of God?
I unfortunately don’t have time to try to go through all the responses to this old canard. Plus, I’m not a philosopher - here’s a site for starters that does an adequate job. There are probably a hundred others:
http://www.godandscience.org/apologetics/who_created_god.html
All I need is your honest answer that you can’t make a reasonable response to this question. You gave me that. If God needs no explanation logically, then, equally logically, the Big Bang needs no explanation. If God simply “is”, the Big Bang simply “happened”. The logic is equivalent.