16 Year Old, Male, White.

Around September Last Year, I had swollen glands and tonsils and earache. I went to the doctors and then this doctor gave me some Phenoxymethlpenicillin. My tonsils and other symptoms went away. 

About 5 months later I went back because my lymph nodes were STILL swollen. My GP tested me for EBV and did a FBC. I came back possible for EBV but my FBC test was re-ordered. I never did the secondary blood test because I was busy

Today my doctor's office message me saying to book a "routine appointment" with my doctor. My nodes are still swollen in my neck.

Should I be worried? Should I go to this appointment? Should I be worried?