IF -- and this is a big IF -- the symptoms you describe are due to asthma, then what is happening are changes in the immune system. Your immune system is designed to protect your body from disease, invaders and harm. Cells such as white blood cells, eosinohils, mast cells, and others that are found in the bloodstream, lymph system and organs such as the spleen are tasked with either blocking "invaders" or seeking them out and destroying them.
Unfortunately, in people with asthma and allergies, the immune system misinterprets normally harmless inhaled substances such as pollen, dust, and mold as threats and initiates a series of (over)reactions designed to protect your airways from harm. These reactions are a tightening & narrowing of your airways, swelling of the airways, and increased mucus production in your airways. All of those changes contribute to the hallmark symptoms of asthma: coughing, wheezing, chest tightness, and shortness of breath.
If you are having the symptoms you describe above and you haven't been diagnosed yet with asthma (or something else), then it's important that you talk with your doctor about how you are feeling, so that you can be evaluated. If you already know that you have asthma, but are still having those symptoms, your asthma may not be under control. If so, you may want to consult with an asthma specialist, who can get you on the right treatment for better control.
To your health,