Hello there ,
Thanks for writing your query,
According to your symptoms i suspect your palatal mucosa of hard and soft palate are inflammed , may be due to allergy to certain food stuffs , physical or chemical trauma , allergy to smoke etc.
It may be caused due to several reasons like deficiency or certain vitamins especially vitamin B12
and vitamin C.
Maintain good oral hygiene
by practising regular mouth rinsing with lukewarm saline water or antiseptic mouthwash like betadine or chlorhexidine
start with multivitamin
supplements for 7 to 10 days and vitamin C lozenges will help in resolving the problem.
avoid alcohol , carbonated drinks , tobacco chewing
and smoking as these may worsen the area affected.
Apply oral antiseptic ,analgesic ointments like dentogel or mucogel topically over the affected area
i hope this helps ,