Painful/Tender Gland Under right side of Throat/Neck

I have had this painful gland under my chin area on the right side for a couple of months now. I've seen 10 specialists, 3 ENT doctors, multiple blood tests, endoscopy, ct-scan, MRI, and they cant find anything. Sometimes it doesn't hurt, but sometimes I get very painful feeling and my gland seems tender, its very very painful to touch, and it just bothers me a lot. The doctors have even done a NASAL endoscopy, they cant find any tumors or anything. I was wondering, what else could this be, it's very painful I don't know if i should get it biopsied or get it removed or what, i can't stand this pain. someone Help!