It seems from your symptoms you are suffering from gastric esophageal reflux disease.
The causes related to you may be having excessive carbonated drinks apart from this cigarette smoking
, having spicy food, having exceesive meal before bedtime. Lying down flat as soon as having food.
GERD causes burning sensation, heartburn
, severe pain
which worsens on bending or lying down,
Tightness in chest causing difficulty in breathing.
Usually this symptoms are relived by antacids.
Now for treatment you need to take proton pump
inhibitors like Pantaprazoles etc atleast for 6- 8 weeks daily.
Avoid those precipitating factors mentioned above.