I think you need to see an electrophysiologist and see if they can correct your "erratic heartbeat", and I am telling you this from experience and I also am a registered nurse. I am 42 yrs old.
When I was about 20 yrs old I started having what was eventually diagnosed as
PSVT or paroxysmal supraventricular tahcycardia. I ended up in the ER about 4 times with a
heart rate over 240. The ER doctors in 2 different hospitals over a 20 year period prescribed me
Xanax and
Ativan for what they believed were panic attacs. I took beta blockers and was on higher and higher doses of
Inderal. My heart still beat crazy fast and I was an emotional wreck. I finally went to see an EP doctor whose name is Kreigh Moulton MD from the Prairie Heart Institute in Springfield, Illinois and he immediately diagnosed my problem which was AV node re entrant
Tachycardia and did an ablation on my heart on October 11 of last year and cured me. I went thru hell before I met this doctor. I was afraid to go anywhere or do anything because I was scared my heart would start beating stupid and I literally thought I was going to die. Please see an electorphysiologist for treatment of your problem. I still dont know why my heart doctor did not schedule me for an appointment with him earlier, but I am fixed. I feel re-born and if you call Dr. Moultons office, I bet he can refer you to an EP cardiologist in your area.
Also, you could be having paroxysmal atrial
fibrillation which can also be corrected with an ablation. No matter what, you need to see an electropysioligst in Cardiology. They can diagnose and fix your problem.