Thats a bit concerning. Be sure to show those EKG tracings to your cardiologist.Many of the medications you list can can affect heart rhythm and interact with each other. The Vyvanse particularly would not be good to take if there is a question of atrial fibrillation.
An EKG I performed while having palpitations showed Afib, which is why I started trying to get different lead readings  was trying to see if it was a fluke or not and get as much info for cardio if necessary (Holters suck). Didnt happen consistently when performing recordings back to backsome would say it detected Afib and others sinus.