Very painful white bumps under tongue and smaller white bumps (less painful) on left side? hurts to eat, talk when tongue goes over teeth

Canker Rancor: Aside from a food sensitivity or maybe a virus,it sounds like canker sores("apthous ulcers").No one knows the cause but boy,do they hurt!! And they can last a long time.Do some Googling and you'll find all sorts of home remedies.Good luck.My bias is to frequently apply a strong steroid cream.You'll need an prescription for one. Apply a lot with a Q-tip and try to keep it there as long as possible.

Mouth ulcer: This is something that needs to be checked out by your dentist. Oral lesions are hard to describe/diagnose without seeing they first hand. Some even require biopsy to diagnose (although this is only a few percent of the time). Go see your dentist and get this looked at. Chances are it's nothing serious but you need to get it looked at to ease your worries and put your fears to rest.