Just keep doing sections, mark the problems you got wrong, find out how to do them. I think the study guide books are actually helpful and worth purchasing-- ask upperclassmen!--because they include tests, answers & explanations, and most include all the info & topics you'll need to know per subject. It's all pattern recognition, 100%. Once you do enough problems you'll look at one and say, "oh thats that problem" and not waste time trying to figure it out. I used to test myself by doing the first 10 problems on the SAT in under 10 mins, to make sure I'll have the easy ones cleared on the test and still have as much time as possible. That's all I got, and I'm sure you'll do great- just dont panic! And let us know how you do!
DUDE! CONGRATS!! So your composite must still be solid overall, and if you have the time I'm sure it wouldn't hurt to 36 it all around since yoire clearly capable.