Hello and thanks for the query
These type of symptoms are either due to anxiety
or problem in conduction system of heart. You are sure that anxiety was not the cause. Now the only thing left is PSVT
or AF (Atrial Fibrillation
). To get to a diagnosis you have get your EKG done at the time of episode or get your 24 hrs holter examination done. But make sure that the episode occur when holter is applied.
These symptoms can be controlled by medications like Beta-blockers or Calcium Channel blockers. If the oral medication fails than ablation may be required.
So consult your Cardiologist and get to a diagnosis.