I think I have ADHD/ADD?

I'm not really hyper or impulsed to blurt things out or anything but its hard for me to focus on anything, people usually have to ask me a question twice because I stare into space a lot. My mind wanders and I daydream a lot. It sometimes takes me awhile to process what people are saying when I used to be more.. aware or something. I don't get bad grades... I have a 4.0 GPA but I think I have ADD... the more not-paying-attention part. I'm also fidgety and I'm sorta moody.