I have shingles and have had it for four days and it still jhasn't blistered or erupted---just itchy and painful will it go away faster or not blister?

Shingles treatment: Assuming the diagnosis is correct, you should be on treatment, e.g. valacyclovir, which will speed healing. Even mild cases normally should be treated; a mild start can still go on to a fairly severe or prolonged course. With treatment, it should stop getting worse in a day or two and begin improving a couple days later. If not on treatment, contact your doctor ASAP. Good luck!