Welcome to QuitTrain, blissvixen, and congratulations on how far you have gone with your quit so far.
Insomnia can be quite common with quitters in their early stages. There are other side effects that some people experience as well. But you are doing a good thing in quitting.
I can't give you advice on heart issues, though. I don't recall experiencing that. I can understand your hesitancy in seeing a doctor during covid but if there is some way to discuss these issues with a medical professional virtually, I would suggest that.
Congrats again on your quit. It is good to have you here.