Accounting Quizzes

I am very frustrated right now.  I just finished taking my second accounting quiz online and for the second straight time, I got a four out of five score, missing the final question.  I realize that these are small, five-point quizzes and that missing one point on each of them isn't a huge deal, but I am disappointed because I honestly feel like I know the material.  I understand all the principles and can explain it well.  For some reason, though, I just haven't been performing well on the quizzes.  My last one - today's quiz - was the kind of thing where I originally put the correct answer and then second guessed myself.  Before I changed it, I made myself or put in words why the answer should be changed.  I changed it and then got it wrong.  Man, I know I can learn accounting and I feel like I really already am and so I really hope the quiz and test scores start reflecting that.