To add to usna1985, the presumption here is that your goal is to be commissioned as an active-duty officer, not just attend USNA. So yes, if you don’t get offer of appointment this time around, try again next year and the year after. A significant chunk of every plebe class was not “direct appointments,” i.e. straight out of high school. And make sure you’re working on Plan B, i.e. NROTC scholarship at a civilian college. If you get one, you’re on your way to getting a commission. And you can still choose to reapply to USNA, this time with the added benefit of having NROTC on your resume.
As a “late bloomer,” you’re not alone. Know it will take hard work, but you have several options to achieve your goal.