WTF? (Click through to a platform that plays this moving gif) One moment you are just you, and then suddenly you are lots of you. Like suddenly you have identical twins, well, triplets, no, er, sextuplets, no, er, well multiplets.
But each one of you has all the memories and experiences of each of the others until you, er, multiplied. From that point each one of you will have new and different experiences, causing each one of you to grow to be different and an individual.
However, is one the real you, or are they all the real you?