So after calming down, doing a bit of self reflection, and doing a bit more research, here is what I found: As long as your application has not been reviewed yet (because you haven't submitted your secondary, LOR, etc) despite submitting your primary app, there is still a mini grace period to make changes by sending the schools an email detailing the change you want to make. Basically, the best scenario I mentioned. This means I have nothing to worry about.