My mom worked for a doctor and saw a lot of people with shingles. She knew the symptoms. She had them and figured it out as soon as she woke up with sore places on one side of her neck.
She went to the doc in the box that morning and got a shot and pills for it. The doctor told her every hour someone is treated under the 12 hour mark after symptoms appear, the better off they are.
Mom had some pain and itching, but overall, she had a very, very light case -- mostly because she figured out what was up and went to the doctor that morning. Early treatment is really important if you even think you might have shingles.