I think I have ADHD...all the symptoms applied to me

My best friend says that I have pretty bad ADHD, and that she's noticed it for a long time. I believe her because we've been friends for 9 years, and also I looked online, and realized that all the symptoms applied to me. I'm only 13, and I don't want to talk to my parents yet, until I get confirmed on here at least. I'm pretty surprised that my parents don't notice it, because all the symptoms seem to happen frequently (when I realize they're happening). I can't seem to stop them, either. Especially finishing chores, and getting distracted. I also have emotional fits occasionally, mostly when I can't finish something. My mom says I'm really pessimistic, too. I pay attention to every little detail (often in homework). I always seem to bury myself in my thoughts and daydreams in class, and then I miss something that I should be learning. I also want to learn, turn my homework in on time, and be a good student (and daughter), but I just can't help it!

Help!!!