You perhaps had panic attack which is characterized by few symptoms like sudden onset of racing of heart beat , sweating tremors dryness of mouth choking sensations  feeling like going to mad or die due to heart attack. Though these synptoms readily recovers within few miutes to 1/2 an hour. But following it patient lives in fear of next attack. Sometime he stops going to crowded places and to travel alone that it would be difficult to escape those situation easily and who will take him to a doctor. This is kind of anticipatory anxiety. You consult a psychiatrist and proper psychotherapy and medication will help you out.

See the evidence base treatment for anxiety disorders are Medications and therapy...So Consult a psychiatrist for detailed evaluation and Management of the case...it will help for sure...You can direct Consult also via practo... Regards