Hello, You have a history of smoking since 4-5 years. You have been diagnosed with bronchitis. Now you are experiencing pain in your chest & back with nausea associated with loss of appetite. It looks like due to loss of appetite you are not staying well fed or well hydrated. You are developing acidity (GERD). For relieve you can take PPIs, one sos when needed. Avoid fried food, junk food. Take substantial food. Avoid taking alcohol in empty stomach. Smoking inflames and irritates the lungs, hence you are having irritation and coughing. Smoking can destroy your lungs and lung tissue resulting in less oxygen to critical parts of your body. Get connected to a detox center & quit smoking at the earliest. Detox center will help to manage withdrawal symptoms. It help weaning from smoking successfully. You are suggested to get clinically examined by a GP, get investigations & imaging tests done to detect if you have pleurisy since you are having chest & back pain. Pleurisy is inflammation of the pleura. This inflammation can make breathing difficult and cause a sharp pain that can spread to the shoulders and back. If left untreated it can also cause shortness of breath, coughing, and a fever. Get treated at the earliest, take home made balanced, nutritious food. Hope I have answered your queries. Let me know if I can assist you further. Take care Regards, Dr. Nupur K