Swollen lymphnodes all down front left side of neck/ear and sore throat at night for several weeks. fatigue and some achiness follows. what is it?

Lymph nodes : generally means inflammation or some chronic infection like virus or atypical bacterial infection, but more serious conditions such as lymphoma need to be ruled out if persist for more than 8 weeks. You should see a doctor, perhaps infectious disease specialist for routine blood tests. May also need a lymph node biopsy. Don't delay evaluation