Whether they'll tell you why you got waitlisted depends on the school's policies. I don't think it is necessarily a bad idea to inquire, you probably won't be able to change those aspects of your application until next year's cycle. This is because the school likely either has a waitlist to fill declined spots or because they're waiting to receive your grades from last semester. Either way there is nothing you can do for this application cycle, but since I don't know what school you're talking about it may be an exception!
Also, applicants can almost always improve every part of their application package. For example you could improve your PCAT composite and GPA, get pharmacy/research/volunteer experience, revise your PharmCAS essay, and work on interview skills. Basically, go through all the parts of a pharmacy application and think of how you can make yourself a more attractive candidate in each area.
