Hello. Welcome to HCM and thank you for your question. I understand your concern. After I have carefully read your query, I can take the liberty and say that you are a perfectly healthy and normal 23-year old. Even if there was a cardiac cause your problem, all the tests you have done, even merely an EKG, would have revealed a condition. All the things you mentioned, point to a classic general anxiety disorder associated with panic attacks. All types of anxieties, even fear, have one feature: a spike of adrenalin and noradrenalin levels in the system. Everyone who has some kind of anxiety, this phenomenon happens and produces its symptoms: shortness of breath, fast heart beat and spike of the blood pressure. I do not think captopril was needed at the time. Panic attacks in people with anxiety disorder, do not have a known cause, but they can be triggered by one s thoughts about dying or something terrible is going to happen, and certain ambient, circumstances and venues, such as speaking or performing in public, being in crowded places where one s perception is that if something terrible happens they do not have how to get out etc. At this point, you should see a psychiatrist, to carefully evaluate this situation, and I would recommend you to be put in a combination with a benzodiazepine and an anti-psychotic drug. Please bare in mind that general anxiety disorder is not a disease, it is merely a situation, but when it effects your quality of life, it should be treated with medication or other popular methods. I hope I was helpful with my answer. Good day. Kind regards, Dr. Meriton