well i can totally understand the organic side since u havent taken the course yet but to save you some time... i would hope u are not taking the test anytime soon because it takes time to really ingest all this material.
secondly, do not feel bad about the test score because i did terribly as well my first time around during my Kaplan courses.
I would really get a strong hold on all the sciences and study EACH chapter solid for now than so that your better prepared.
i hope this helps...
But seriously, do not feel bad about your practice test because you have to re-study/review the old notes...