I really think that I am too smart for my own good.
Why do you think that you are too smart?
I just always think that I am right. I guess I am stubborn.
It's great to be confident and believe in yourself. That said, you probably shouldn't be cocky about it and make an effort to not be as stubborn.
Ok
It is great that you are self confident! Just remember that you need to also consider the opinions of others as well, as hearing what others say and think will allow you to learn and adapt.