Sounds like you're thinking of majoring in science--you should probably retake the classes, especially if you're going to a very good college.
You might want to rethink taking physics, bio, and chem in the same semester. That's a pain and probably not something a first semester freshman should do....You're gonna want time to adapt, make friends, stink overcrowded dorm room rompfests, whatever.
Chem will be time intensive no matter what. Bio is straightforward but might need some study time. Physics will depend on whether you can grasp it--could be your easiest or hardest class.