(((Dizzy man))). Really sorry you have had to endure this.
Only reference I have on this is from what happened to a friend. Sounds like you've gotten past the blister phase, but there is a cream called Zostrix (sp?) that you should be able to get over the counter. Don't know if it would help you now, I'd ask the pharmacist.
Other thing that was prescribed when blisters became obvious was a dose pack of steroids. That helped with healing & pain. Seems like there was an antiviral med he took by mouth but can't be sure on that one. Best I can remember nothing he took for pain worked either.

Don't know if this helped, wish you the best.