Thanks for trusting HealthcareMagic for your query.
On the face of it, your description appears like 'panic attack'- a psychiatric condition where one gets the sudden onset of symptoms described by you and subsequently the fear of death or fear of becoming 'crazy' is so intense that person has no other options except to visit emergency department. In such condition person becomes very fearful of having another such attacks. They also tend to avoid the situation, places or activities where they anticipate any such attack can occur. So, their life gradually becomes very restricted and they feel suffocated within themselves. To a layperson, they may appear normal but the person suffers a lot within himself or herself.
Given that your brain scan seems to have identified some benign lesions, a good idea may be to get a EEG done which can figure out if there is some underlying 'seizure' to explain the phenomenon.
A good idea will be to consult your nearest psychiatrist
who will help you understand your problem and discuss various ways of managing your problem.
Hope this information will be helpful.
Dr. Amardeep Kumar