hello.Thanks for your query
You have been started on the correct medication and in the correct time.You have to complete the course of this medication as advised.It takes 2 to 4 weeks for the blisters to heal.
Since this is known to be painful condition, you can have oral anti inflammatory medication to relieve the pain /burning sensation.A soothing calamine
lotion can applied to comfort the area as well.It has to be borne in mind that these treatments are supportive and are only meant to lessen your discomfort due to shingles
Hope this is helpful.Wish you speedy recovery!