Hi welcome to HCM.... Here According to your history the chance of allergic respiratory infection is more by cold ..... Asthma had to be ruled out here..... For that pulmonary function test done.... Spirometry done for it.... If asthma confirmed then keep metered dose inhaler handy of salbutamol .... When dyspnea it can be taken for bronchi dilatation.. Avoid contact to allergen..... Cold exposure kept minimum... During congestion antihistaminic might useful .. Steam inhalation also good one.... You can mix one tsp ground ginger in half cup of water and one tsp can taken at bed time before sleep that is good herb.... Keeping these in mind consult pulmonologist for detail workup.... Take care. Dr.Parth