Re: Coughing, trouble breathing, clear Xray?
The symptoms you describe and response to treatment are suggestive of asthma, which causes bronchial spasm and inflammation. The bronchospasm can be brought on by cold air, damp air, smoke, pollens, pollution, fumes, infection, allergens (like cat hair), dust, etc. plus exercise induces it in some people. There are pulmonary function tests that are used to help diagnose it, and many forms of treatment are available to prevent the spasm, not just relieve it once it is occuring. A pulmonologist should be consulted, and I would do that now. Rescue inhalers like albuterol are often not enough, and prevention is a better approach. Staying away from known allergens, dust, smoke, etc is a big part of treatment. Albuterol can be used 5-10 minutes before exercise to improve your exercise tolerance. This should be taken very seriously, as untreated asthma can lead to emphysema in time, which is permanent lung damage that can be disabling. You had a serious attack if oxygen dropped to 68%, and that can happen again without warning. So please see a Dr for diagnosis and treatment to get it under control.