Feeling breathless and suffocated in car esp in heating.what is the cause? this never happened before. feeling hyperventilated.normal bp and pulse.

Shortness of breath: You should visit your physician for a full exam. If you are experiencing shortness of breath, a full workup should be performed. Does your shortness of breath happen during exertion? At night? With certain triggers? You are a woman of childbearing age-need pregnancy test. After a careful history, vital signs/pulse oximetry and physical exam, other tests like spirometry, EKG, ABG, CXR etc Good luck