Prospects for college?

<p>I’m a junior in high school and I’m sort of new to CC. Anyway, I was wondering what you all think about my prospects for getting into a good (prestigious and rigorous) college. I went to an IB school and made straight A’s for 9th and 10th grade and now I go to NCSSM (high ranking boarding school with hard application process). I am in difficult classes and involved in research in Computational Science (Jackson Genomics Lab in Maine), have strong leadership positions (SG, Residential Life Assistant, officer of clubs, etc.), and many extra-curriculars/competitions (AMC/AIME). My SAT is 2250 but I will take it again to improve it, and my PSAT was 225. The only thing that worries me is my grades. We have trimesters so we get more grades than normal high school and I have all As (after two trimesters-9 classes) except 2 Bs and a C. I can get all As next trimester and fall of Senior year but how badly will those 3 grades effect my chances? I want to go to a good school and study pre-med but I’m very stressed out about my grades. What do you all think?</p>