There are an infinite amount of possibilities based on how random our universe is. I assume you've read about the plausibility of multiple dimensions where at any one time your current self could be acting upon ANY decision you could think of. Also, as soon as you think of a decision or choice...that actions is carried out within another universe.
An example of infinite possibilities and variations is:
When you were a kid you broke your arm. You later found out that the bone may never heal correctly. You had to drive across state for a surgery, during which a family member died. This event traumatized you and tormented you through your life and into adulthood. You one day snapped and committed suicide.
This all happened because you broke your arm when you were a kid. Your arm could have been protected if you would have gotten a cold and decided not to go out an play on the swings.
This is the Butterfly Effect.
You may not have a wart on your nose, but if you would have touched that handrail while going down the stairs a few months ago...who knows.
And about the universe not being infinite; who knows quite yet. The WMAP has just taken a picture of the Big Bang, that is all you have to play with in terms of our cosmological timeline. Some say the universe is flat, but again who knows -- it could curve back onto itself or possibly deflate and start again.
Wow. What a mix up you have exhibited between science fiction, chaos theory, quantum mechanics, butterfly effect, probability and chance.
While there is no evidence for multiple dimensions/universes, I can only live in the present - and although there is a possibility of something, it does not mean that it is an inevitability.