Mike, Ben here,
I'm not a doctor, so no matter what I write here please remember that. I tend to see things in black and white and sometimes it sounds like I know too much not to be one. With that said, BPPV and VN are not even close to the same things.
BPPV is a loose particle that can be put back into place by a maneuver, like the
EPLY or 1/2 somersault. VN is damage to the Vestibular nerve that requires exercises and a lot of time to repair.
BPPV can be arrested immediately by doing one of the maneuvers. If done correctly, the spinning that BPPV causes will be gone instantly. Vestibular neuritis takes repeated exercises over a long period of time to retrain your brain. The relearning is called compensation. The exercises can be looked up on the internet and on youtube under their respective names. I would give you several urls but the moderator will hold up my post to you until they are checked out for maliciousness, which could take some time, and they are easy to find anyway.
Meanwhile you could be doing the maneuvers yourself and make instant recovery for BPPV. If you do the exercises for BPPV it will not hurt you if you have VN, just make sure you don't fall down or fall over, because they do tend to make you more unstable for a few seconds. The BPPV maneuvers, like Eply or the 1/2 somersault, will not affect VN, so don't worry about that.
The exercises for VN will not do anything for BPPV, they will just be a waste of time. VN is a whole different ballgame from BPPV. You have to walk heal to toe, walk looking up and down and side to side, looking far away and then up close. Standing on one foot and standing with both feet close together, eyes open and closed. Looking at cards with letters on them set several feet away, at arms length and up close. Rise from seated and sit from standing. There are more too. Remember, VN exercises work your eyes and help you relearn to use the damaged signals coming from the Vestibular nerve.
VN is the one that causes double vision and shaking eyes called Nystagmus. It can give you quite a headache, and trying to function doing daily things will cause fatigue. You will become very tired and need to rest. There is no accelerated method to make recovery faster. A regimented schedule that is methodical and repeated for short intervals is the best way to get back to normal. It is going to take longer if you don't do them, but it won't speed it up if you try to do too much.
So, look them up under their names and get started on the maneuvers and / or exercises. Just be careful and work methodically and take the time to spread out the exercises.
Good Luck to you and be patient, you will get over this, it just takes effort and time
Ben