Sir the symptoms that you are describing is suggestive of involvement of lower end of esophagus( food pipe) or stomach.
The diseases that may involve the above said organs leading to pain right after meal can be
1. Reflux esophagitis
2. Acute/
Chronic gastritis 3. Gastric ulcer
4. Gastroesophageal reflux disease
5. Small gastric or esophageal erosions
The CAUSES of the above is multifactorial and includes
1. Hot spicy meals
2. Excessive intake of caffeineted drinks
3. Eating smoked foods
4. Intake of alcohol and smoking
5. Infection with a bacteria H. pylori
The TREATMENT of the same includes
1. Avoid hot spicy foods especially empty stomach
2. Multiple small meals
3. Avoid oily foods
4. Take Cap Pantop
DSR before breakfast daily for a week
5. Syp
Mucaine gel 2 tsf thrice daily for a week
6. There is a specific treatment for H pylori called
HP kit twice daily for 14 days that can be started after one week if no relief after one week
7. Upper GI
endoscopy may be planned in due course