Re: Shingles vaccine at 22?
You don't contract shingles.
When you were smaller you contracted the chicken pox virus . Some of the virus stayed lodged in your nerves hiding away. When people have a low immune system the virus turns into the Varicella Zostre aka Shingles. So it's sort of a mutation of Chicken pox. Low immune system can be caused by stress. Stress causes you're body to work overtime, this means that the defenses that were keeping the shingles dormant are now busy elsewhere. Hence you get get a reactivation of the virus.
The stress can be emotional too, so try relaxation techniques. Although in your case, probably blood caused your defenses to go down to fix that wound.
As for getting the vaccine well they recently lowered the age from 65 to 50. Mostly older people get it because they have a lower immune system. Ask your doctor. I also suggest now that you've had shingles you look out for the clues ( itching, red area, feeling nerve pain, etc) that indicate that you're getting it and run to the doctor. Ask for a shot of B-12 , this will make the shingles last only a couple of days and wont really hurt. The shot has to be taken before the outbreak of the actual outbreaks, so about max 3 days after the first symptoms.