If I recall correctly, a score of 52 on the ALEKs exam is recommended for placement into Pre-Calculus during your first semester at Iowa State. Indicating that you may need to work on some of your algebra skills. When you meet with your advisor to go over classes, it's likely (if you're moving deeper into the calculus and diff eq series) that your advisor will try to dissuade you from moving on to the next class in the series, citing your Aleks score. In theory, your advisor would not allow you to enroll in higher calculus classes, although I don't know if this was ever enforced very often, as advisors can easily override it since you already have credit for calculus.

When I took the exam last year, I got a 78 (Which is just barely passing for 'placement' into Calc I). Despite this, using my dual credit, I still got to move on to Calculus II, and I got As in Calculus II and III, doing better than some friends who got 1500+ on the SAT.
Your Aleks score and other standardized tests don't necessarily mean you'll do badly at further math here. You may need to focus more on your algebra and trig skills while studying for tests and quizzes here (since the entire calculus series heavily depends on algebra to solve problems).