According to the symptoms you report (chest pain and hard breathing) and in consideration of your age (mid 40's) you should see your primary health physician to get a check up on your heart and lungs. A physical examination, ECG, and probably X-ray images of the chest can be performed. Only when everything is ok with the heart, lungs and thoracic muscles (all tests indicate health)..and only then should you consider anxiety as a possible cause for the symptoms.