Hi, white patches are common in many throat infections. The sore throat which you had may have contributed to it. In response to the infection the body produces soft white debris which collects in the tiny indentations in the tonsils called crypts. Repeated salt water gargles will help. Mix one teaspoon of salt in 1 cup of warm water and gargle. If the patches increase in size or become painful then consult your doctor. Regards.