I was confident that I had aced my chemistry test in college
In college I studied very hard for an upcoming exam that I was very interested in getting a very high score. I was confident that I did so.
user
I'm sure you studied hard and should be proud of that! I'm positive you nailed it.
assistant
I was very excited with my result. I am very competitive. Sometimes I wish I were not so competitive.
user
Being competitive isn't a bad thing unless you let it get in the way of your personal life. 
assistant
You are completely right. It is very important to not lose sight of what is important in life.
user