M.P.
I'm not sure what it is you want to know. I have an irregular heart beat (an arrhythmia) that is benign. I've had a carcinoid tumor removed from my right lung. I think it's the same cancer you had. I've been cancer free for several years now but had to have a chest x-ray or CT scan every 6 mos for a couple of years and then once a year for 3 more years. Are you doing that?
You mention doctors that you've been dissatisfied with but none that you're seeing now. I urge you to find a family practitioner that you trust so that he can refer you to specialists when you need them. I've been fortunate in that I had an excellent GP who referred me to doctors that he knew and trusted. The GP did the follow up visits after the cancer surgery. And when my heart was skipping beats he referred me to the cardiologist. I was feeling stress also at that time.
You really need to be seeing a doctor regularly. At the least, yearly check ups. Find a good family/general practitioner who will keep up with your history and will refer you when you need a specialist.
Stress will cause an increased heart rate and arrhythmia. And an arrhythmia will cause stress. The numbers you give sound within normal range. And I've heard my heart pounding in my ears from time to time. I would find ways to relax and not worry so that you can wait for your appointment. You can call the advice nurse at the cardiologist's office and give your symptoms to ask for reassurance that it's OK to wait 3 weeks for your appointment.
BTW I'm glad you're still with us on this site. And I do remember you from a conversation about carcinoid tumors.