Recurrent bouts of shingles in a young person are rare, and are indicative of an underlying immunity deficiency that needs to be addressed. The cause of a suppressed immune system can vary, and is sometimes insidious. Though treatments for a disease (like chemotherapy) or a medical condition are more common causes of recurrent shingles in the young, healthy teens and young adults can also have a weak immune system. Chronic physical stress due to things like ongoing sleep deprivation, eating disorders, or an injury can batter it. Profound psychological stress can also weaken your immune system. Clinical depression, fibromyalgia, and a vitamin D deficiency are other possible causes. A vitamin D deficiency has become far more prevalent than many people realize due to our modern lifestyles that require more time of the day to be spent inside at work or school, and our use of products like sunscreens that make it harder for our bodies to absorb the vitamin from the sun. I most definitely recommend that you get your levels checked to see if that's a contributing factor.
Though you probably do not need to have a doctor confirm that you have shingles during your recurrent outbreaks if properly diagnosed the first time since it has such distinctive behaviorisms, you do still need to see him or her as soon as possible. Antivirals will tame the beast that is shingles. Early treatment can lessen your agony. Below I am posting a link to a blog I wrote last month about my experiences with recurrent shingles (mine are due to having Hodgkin's Lymphoma), and if you scroll through it you'll find some home remedies that have been beneficial to me.
In regards to prevention you first need to try to identify what is causing your immune system to behave abnormally for your age. When you see your doctor for the antivirals, discuss the situation. Have some routine blood work done, and make sure you ask that your vitamin D levels be checked. Evaluate your lifestyle and consider whether there are changes you could make to help improve your immune system. If you've been undergoing stress, see what you can do to help alleviate it. Strive to get adequate sleep, nutrition, sunlight, and exercise. For stresses that you might not have any control over, you might benefit from seeing a respected professional to help you learn coping mechanisms.
Though the shingles vaccination is marketed and primarily administered to seniors, those under the age of 60 can sometimes get it and benefit from it if prescribed. Unfortunately, though people with weakened immune systems are at highest risk for developing shingles, the vaccine, is often not an option for them, as it is a live vaccine and hence not safe for people with weakened immune systems. This is what my oncologist told me. For you, it might be appropriate. The other issue with the vaccination is the cost since many insurance carriers either do not cover the cost at all or have stipulations about the coverage.
I really hope you can solve this mystery and do not suffer from shingles again. I absolutely am sympathetic to the pain, frustration, and toll it can take on you, and you have my sympathy and best wishes.