While I have no doubts about my own gender, I'm not in a position to answer the "purpose" question. What is my purpose on this planet at this time? I have no idea. So it might be that these are two different concepts or questions to be answered --- or not.
As an example: The yearly review at $dayjob with the oh so useful question "where do you want to be in five years from now?" Heck. I don't know. I'll be somewhere, I guess. There is this bit about the "Zen method of navigation" in one of the books by Douglas Adams. "I follow a car which looks like it knows where its going!". Yeah. You'll end up somewhere. And it might even be a pleasure. Purpose? I have no idea.
Maybe my purpose is to just be happy, maybe I'll make something big and grand, but at the very least I can create programs, stories, and pieces of art for me, my friends, and possibly the rest of the world if I feel like it, to enjoy.
And that doesn't sound terrible.