Dengue Fever and myocarditis with cardiogenic shock

Hi,my son, he is 4 years old now and weighs 14kgs, was hospitalized 5 times in a span of 1 year. 1st hospitalization is due to dengue fever, after 4 mos he had tonsilitis, and during the admission pneumonia and myocarditis was discovered. He was re-admitted a month after again due to pneumonia, he had intravenous antibiotic both for pneumonia and to manage the myocarditis. He was discharged, and found to be okay but we were advise to monitor his heart by taking ECG every month. By April this year, he stopped taking carnicor, monitoring is stopped and the doctor advised to just be on the look out when has a fever. Then by June this year, he was admitted again due to pneumonia with consolidation. Treated then okayed. But after 2 weeks he was readmitted again due to dengue and myocarditis. His discharged sheet shows that he also had cardiogenic shock.
He was transferred to ICU for 3 days but his BP is normal all thru out our stay. He was given dobutamine at 1.6ml per hours. We are already out of the hospital now, but just after 2 weeks he has some cough again. i gave him ventolin syrup, and we nebulized with duavent for 2 days. his cough has improved but still there every now and then. my fear is if this could developed into pneumonia again. should i bring him to the doctor again? what could be the cause of frequent pneumonia and coughing? should i see and find another pediatrician? his pedia advised that we might treat him of primary complex as he is not gaining weight. but 2 previous ppv test are negative. his last ECG shows all are normal except for “mild mitral valve regurgitation”. i read somewhere that sometimes myocarditis is misdiagnosed of pnemonia and asthma or they usually go together? if often stressed because i kept monitoring his pulse and heart rate. i often ask him if he has chest pain, but he never complains even before the diagnosis of the myocarditis. hope you can give some clarifications.thank you.