Hello there,
Well the problems you are facing are typical of a Generalised Anxiety which includes air hunger or feeling as if chest is not completely filling with air or difficulty breathing. First thing to do is consult with a Chest Physician to rule out Asthma and Allergic Disorders. If you have already ruled that out you should see a Psychiatrist asap. Breathing issues are one of most disabling feature of Anxiety. A detailed consultation will be required to find the root cause of your problem.
Next Steps
Consult a Psychiatrist
Health Tips
Do not delay treatment as it can lead to worsening of symptoms overtime.