Cough & cold for last 8 days. In 8 days.

Hi my 9 and half month baby suffering from cold and cough for last 8 days. At the beginning he has running nose and fever ( 100 deg f) for 3 days at that time Dr. Prescribe medicine alegra 2.5 ml for 3 days 3 time and tuspel 2.5 ml for 3 days but condition remain same and 3 days later he started wheezing havely then Dr prescribe nebulizer ( leulin and deulin) on sos basis. 4 days past by giving him nebulizer (3 times a day) and medicine but cold and cough still there and breath heavely, because of this he is not able to feed ( top and brestfeed) and sleep well. We hydrate him well pee count 20 + times a day He also have tiny closing vsd from birth. Pls suggest what we can do his weight is also decreasing around 400 grms in 8 days.