Big bang question - Dumb perhaps

OK, now don't kill me on this, but what I'd like to know is this:

We know the Universe started with the Big Bang. That's all fine and
good. But I just can't help thinking that time had to exist before the
bang took place and whatever that thing was that exploded had to take
shape and form much before. If so, time really goes back a long way
before the big bang and so does the Universe. And technically, this
equation could go on till Infinity... which is the real kicker because
it practically means that nobody will ever know how it all began. Am I
making sense or simply missing something?

This may really sound amateurish (if a reasonable explanation exists
and I'm not aware of it), but I can see that there are people here
that may be able to satisfy my curiosity on this one.

Thanks a lot

Rohit