How would you rate yourself as a writer?

In today's English class we were asked to write a "prompt" on our most vivid memeories of being a writer. The first memory that popped into my head was one from sixth grade. My story went a little thing like this: 'We were told to write an essay about our favorite Thanksgiving memory. I knew immediately what I wanted to share with the class. My mother is one who loves to cook, so any holiday was an excuse for her to whip up an extraordinary dinner for our family. As I began to write, I shared the story of how my mom is the best cook because she can cook her turkey so that it has both white and dark meat. Although I understand now why the class went hysterical, I was quite confused at the time. My teacher laughed at my story as well, but when she handed the paper back to me, I had gotten an A. My story may not have made sense, but I received a comment saying how well written my essay was. Ever since that moment in sixth grade, I have had a passion for writing. I can’t say for a fact that if it wasn’t for that essay, I wouldn’t like to write, but after receiving that comment, I found that I had the confidence in myself and began to believe that I really was a good writer.'
In sixth grade, and even up until high school, I actually believed this to be true. Then I started taking the survey in English today and I read over the question 'How would you rate yourself as a writer?' Naturally, I circled solid/good. I figured very good or even excellent would have been pushing it just a little bit...I was certainly correct. Following that question was one that read 'How would you describe the difference between "formal" and "informal" writing. Give a couple of examples.' My mind suddenly went blank. Of course I had some idea as to what the difference was but I didn't really have any good answers to give. In all honesty, if I was such a good writer, the answers and examples would have come to mind immediatly. Now I'm not saying that I just realized at this moment that I am a horrible writer, but I think now is the time I am starting to evaluate what kind of writer I am. Although I didn't change my answer on the survey, I am telling everyone now that I would rate myself as "good enough." My goal is to leave this classroom with enough confidence and skill to circle the word "excellent."