Me Who is a Scary Fast Reader

Heyo! I haven't posted in like 2 weeks sorry. Anyhow I realized this: On all the books I read it has a "J" and then the author's name, for example, J MASS. Now I am reading a book that says YA MASS and has a little young adult sticker. That means J is juvenile and YA is YOUNG ADULT!!!!! Am I an 8 year old young adult? Scary stuff. By the way, the book I'm reading is A Mango-Shaped Space and it's very good. You should check out other books by Wendy Mass!