Thanks for your query
Your family physician has rightly said the mantoux test
is only suggestive and as you had TB in the past mantoux test quite usually can give such result. It doesnot mean TB. You may go for a chest X-ray though i think it will be little contributory as there is already lot of fibrosis
. Your sputum is already negative for AFB. In this respect if there is high suspicion of TB then its better to go for BACTEC culture of sputum because it is gold standard. Another test in this clinical context may be vary useful that is TB DNA PCR. If these are positive it will be better to start ATD.