Here is one way to process it.
Nominations are full of "exceptions-to-the-rule". You will hear this person got this, that person did that, my MOC and Senators did this or that...and then hear a myriad of variations and exceptions, all subject to whether that person's story is even accurate at all, or if they misinterpreted their own nomination journey.
With that said, complete your USNA application with quality effort. You cannot optimize your nomination knowledge, only satisfy yourself that you applied to every source, INCLUDING the VP nom. If there is more than a 0% chance you would go to USNA if ultimately appointed, then keep your portal open. And I would say that's a yes, since you don't have an appointment to USAFA yet AND even if/when you do, one of the "risks" is that you become medically disqualified at USAFA, but through waiver process would be qualified at USNA and it becomes your only SA option. If there is more than a 0% you would then go to USNA - for that reason complete your application, and wait if you get a nom and appointment.
Optimize:
Apply to all your nom sources
Finish all your applications with quality effort
Carefully order your SA choices
That's it. The rest you can only be satisfied with any noms you get, and keep your SA portals live and open until the end. You will spend useless energy worrying about the Nom That Got Away. Don't do that! Channel your energies elsewhere, and right now you are entering......Scholarship Season! Go search for scholarships, work out, embrace being a high school senior. CLEAN YOUR ROOM! hahaha, no seriously, it's also a good time to clear out your room and get a big box of Things I Might Want My Mom to Mail Later.