Do 7th Grade CST's make a big difference in your entire life/career?

I am a 7th Grade student in California. I want to become a lawyer when I am older. However, my family and I have just moved from England and because the education system is different in England, I have not learned a few of the things that my classmates know, but I also know a few things that they don't. I have come at precisely the wrong time, because all of the tests are in a week and I am obviously not prepared. As I mentioned earlier, I want to become a lawyer and I am wondering if me doing bad on the 7th Grade CST's will impact my life or career when I am older. Also, if you know of any helpful courses to take in High School or College. Thank you for answering my question.