Anxiety itself doesn't let you believe that it is the culprit behind all the symptoms .It is very necessary that you should listen to your your doctors and take it seriously, however this issue is treatable just follow the instructions of your doctors and if you are not satisfied with their approach then you always have an option of second opinion.
Next Steps
follow your doctors advice and believe him or her.
Health Tips
if there is no physical cause than probably it is psychiatric illness.