I am not sure where the
glands are swollen.
Neck lymph nodes can be the result
of tonsillitis, pharyngitis (infection
of upper throat), infection in mouth, caries in tooth, internal ear infection, outer ear infection, eczema, dermatitis, dandruff, breast cancer, fungal infection, other cancers like lymphoma etc. If you had flu like symptoms initially then it could be due to infectious mononucleosis too.