Before the skin rash there can be peripheral nerve related symptoms, it could be either pain, numbness, itchiness or a burning sensation, each one of them is a typical peripheral nerve related symptom.
Shingles are blisters, at first they may appear not fluid-filled, then in days they develop into blister-like sores filled with a clear fluid. The pain can be sharp, stabbing. You can feel both pain and itchiness, however, pain is more severe.
Shingles appears only on one side of your torso, it's because it goes along the peripheral nerves which are unilateral distributed. Occasionally people can have Shingles on both sides of the body, it happens when the virus invades the nerves on both sides of the body. It's like one gets both hands cut by a knife, which is possbile but rare.