hi and welcome,
After reading your history i suspect you are suffering from oral submucous firbrosis ,OSMF.
It is inflammatory condition of the oral mucous membrane
caused due to chronic tobacco or bettel nut chewing habits.
This condition is characterized by formation of fibrotic bands of oral musculature of cheek and lips which leads to restricted mouth opening and senstivitve areas to hot and cold.
i would suggest you to consult an oral surgeon and get the evaluation done .
Treatment for OSF definitly needs quitting the habit of tobacco chewing
and alcohol. avoid hot and spicy food.
Intra steroidal injections along with the course of antioxidants will help you out.
Antibiotics have no role in treating OSF . i would suggest you to start with LYCOPENE
2000MCg tablets two times daily for 15 to 30 days .
For red sores and ulcerations you can apply topical dentogel over the affected area and use chlorhexidine
mouth rinse as an antiseptic.
i hope this helps,