Hello @lalaag, and welcome to Mayo Connect - I see that you are new here. We are a community of people living with a wide variety of conditions, coping and helping each other along the way. We are not medical professionals, so cannot provide medical advice, but we can and do share resources and what has worked for us.
Shortness of breath is a frequent symptom, which may or may not have an obvious cause or diagnosis. It has been an issue for me through many years, and my story sounds a lot like you - asthma, allergies, stress, heart disease... - yes, no, maybe. I was finally diagnosed with a lung condition called bronchiectasis during a massive lung infection, which means the bronchioles do not function properly, lungs tend to fill with mucus, and opportunistic infections occur. My brother had a similar experience, and ultimately received a different diagnosis - now we each have an appropriate treatment regimen, and life is better.
What has helped my shortness of breath is daily use of my meds, practicing deep breathing exercises and airway/lung clearance techniques and avoiding ill people because every cold develops into bronchitis or pneumonia.
You mentioned seeing a cardiologist, have you also been evaluated by a pulmonologist?
Sue