How important is testing?
While it is important, it may not be as important as you think. Firstly, grades in school, especially in HL classes, is always number 1.
What college admission officers say:
Over 800 US colleges are test optional
Scores are also contextual; Take a careful look at the mid-50th of the scores of student at a particular college. This site does a nice job for both SAT and ACT: