Thanks for writing to us.
Neck pain below jaw line can either be due to throat infection
or due to abscess developed as a result of deep caries or periodontal infection
I would advice you to get a thorough clinical evaluation by a dentist
as well as an E N T Specialist.
Infected tooth has to be either root canal treated or extracted.
Complete course of antibiotics as well as analgesics has to be administered.
Gargle frequently with lukewarm saline.
Hope this helps.