Hi, dry cough with normal chest x ray suggests upper respiratory tract
infection or reflux pharyngitis
or asthma or COPD. Since the symptoms are getting worse you need evaluation. since your doctor after examination could not find any problem you can try the following with your doctor opinion.
1. Do steam inhalation and hot water gargle three times a day.
2. Do regular breathing exercise
every morning for 30 min.
3. Take cough suppressant syrup 3-4 times a day and pregabalin
75 mg once daily.
4. If you develop breathlessness then take levo salbutamol
inhalation once and when required. These will help you.
To diagnose your problem and to give correct treatment write back regarding your improvement after the treatment and the investigation report.
Hope this helps you.