Hi, its better if you visit some dentist to get the proper diagnosis. keeping in mind the location of ulcer and your age, it can be either - aphthous ulcer, traumatic ulcer. if you can post some pic, it would be better. Regarding treatment, keep in mind that if its traumatic, then using any numbing gel could further deteriorate the condition. as of now just symptomatic relief will better like using ice cubes or any coating agent like sucralfate mouth wash. if nothing is there, use Milk malai to coat it

The right treatment can be advised to you after a proper diagnosis which can be done after a proper clinical examination and not by the description that you have posted..... for symptomatic relief you can apply anaesthetic gels like dologel CT.... Regards....

Greetings. Firstly it's important to know what's causing the ulcer... Whether it's a candidal infection or fixed drug eruption or due to vitamin deficiency or an aphthous ulcer or even herpes. Do not ignore and see a qualified dermatologist near you or send in snaps on follow up messaging. Warm regards