I appreciate you seeking help. Well, the pain
is due to the infection
for which you have been given antibiotics by your doc. The pain will likely subside the sooner the infection/ inflammation gets better. Still, as you are unable to bear the pain, I suggest you to talk to your doc who can recommend a suitable anaesthetic gel that you can apply on and around the ulcer
couple of times a day. Also, cleaning the mouth properly with an antimicrobial mouth wash/ gargle can help arrest the infection additionally. Try taking semisolid/ liquid foods for the time being and stay well hydrated. Avoid any kind of hard, spicy, oily, hot foods/ drinks so as to avert
any kind of escalation in burning sensation/ pain. Hope this helps. You can connect for an integrative naturopathic traction
that can help improve clinical outcomes fast should you feel the issue persists chronically or the ulcer takes longer to heal
up. Do take care, and all the very best.