Lol, it's just that I don't interpret "heavens" as the entire universe. Plus, since time existed only post Big Bang, the concept of "in the beginning" doesn't work prior to it. Which of course means that time already existed at the start of the OT, from the very first verse. But, I have a verse that may help:
Ecclesiastes 3:11
"He has made everything beautiful in its time. He has also set eternity in the human heart; yet no one can fathom what God has done from beginning to end."
Perhaps why no one can do that is because even the very concept of a "beginning" doesn't entirely apply to god because it formed before time did (and said formation could have been the catalyst for the Big Bang), but that would be some extreme speculation on my part. I think it is very clear that the OT only covers events after time already existed.