There’s nothing wrong with being thirteen and vegan; however, make sure you’re getting enough B12. I get mine from a multivitamin
I´m a vegetarian for 2 years now and a vegan for nearly 2 months. My Family (all meat eaters) don´t like the fact that I´m vegan but I honestly don´t care. It´s okay to be vegan. When someone says that I´m crazy because I´m vegan, then I say: I don´t tell you what you should eat, so don´t tell me what I should eat. If you want to be vegan, then be vegan.
I totally understand you; I’m 13 and I’ve been a vegetarian for 4 months, but I want to go vegan. I don’t think it’s a bad idea for anyone to go vegan if you eat the right foods, and you could explain the health/environmental/ethical reasons to your family so they understand your decision a little better