I pretty much started out writing full time. I was an at-home mom and when my youngest entered kindergarten, I started writing. I was 35, and before that I really hadn't written at all. Which means, I guess, that a) it's never too late to start a writing career (or any career you really want) and b) it's OK to get to your mid-30s and still not know what you want to be when you grow up.