My Dr prescribed valtrex for numbness I've been experiencing in my face for the past 3 days. After researching on the web I've learned that what my Dr thinks I have is shingles, a form of herpes.

My concern is this, I've read that a rash may be on the way as well as blistered sores that will crust over. The area of the numbness happens to be my right front cheek, my right side of the nose, upper roof of mouth and gums and my right side of my tongue. Does that mean that all of the areas that are currently numb are going to be covered in a rash with blistered sores?

It sounds just awful, and to think that these will be IN my mouth is just almost too much to bear. I've been on the valtrex along with cephalexin for about 24 hours now and there has been no change. I'm getting pretty worried, since I've also read that numbness can persist for months and even sometimes years. How long should I wait to return to my Dr if the numbness persists?