It is hard to breathe when taking a deep breath and yawning. my chest feels heavy and sometimes it hurts to breathe when i laugh. what could be wrong?

Asthma is possible: The feeling of heaviness in the chest, trouble breathing, and breathing problems after laughter can be symptoms of asthma. In most cases, people with asthma also have coughing and/or wheezing. Muscle strain in the chest muscles or anxiety attacks can also cause these symptoms. If it continues, it's a good idea to have a doctor examine you and figure it out!