Hello this is DR ARPAN,
First i want to tell u not to be panic about the possible severe outcomes of disease.
one thing you can do to avoid infections is to strengthen your chest wall muscles by doing some regular light exercise ,those are possible even at home. It will help you to clear out any secretions that may be due to the initial process of any infections andwhere,the weak chest wall muscles are usually not able to cough
them out . It further intensifies the infection process and destruction of bronchioles which is the core pathophysiology of bronchiectasis
Yes, you can land up in to core pulmonale if you will continue to have repeated infectins but it is not thr rule. so be optimistic and cope with the current situation.
You can continue the theophyllins as per the recommende dose prescribed by your previous physician.