i'm not sure if you are explaining your problem or trying to warn us by saying "Excessive yawning cause breathing problems !"
kindly be clear while posting your questions. also i haven't heard that excessive yawning causes breathing problems.
kindly consult a pulmonologist and get a pulmonary function test done. based on the report of that test a pulmonologist will be able to decide what to do.
Dr. Anil Kumar Jain