I am suffering from swelling and sore of upper palate in mouth area nausea and lil bit pain. is it normal? docter says its oval ulcer.. is it normal?

Mouth sore: Many conditions within the mouth may cause this and most are benign and resolve fully in a short period of time. One very common condition is a burn from hot food not appreciated when caused during later but felt later. Other inflammatory lesions such as ulcers resolve on their own without treatment. If this is not improving seek physician evaluation.