After reading your history it appears that you might have developed allergic dermatitis
to some contact allergen or environmental factors such as dust etc or it may be simple urticaria
too due to water. I advise you to not pinch or pop the area otherwise these areas are very prone for getting secondary infection. You can apply an steroid cream such as cortisone
cream. If itching is present then can take benadryl
accordingly. Apply a plenty of moisturizers over the affected area.