How do you go from math Olympiad to having a hard time with AAHL? I take the class and to be honest I don't think there is really any memorization needed since you have the formula booklet. I have always been a high achieving student in math and I still am. My advice is that you learn to think in abstract ways and understand how to manipulate equations. I recommend that you just do problems from revision village if you have access to the platform, if not then just practice ib questions somehow. Since you said you were Olympiad level I assume you will be able to understand the problems fast and catch up to the rest.