Kevin, you not alone , I too often suffer with AF after sex especially if I edge a lot and mostly in evenings , it appears to be better in the mornings. Now this maybe due to BP as mornings it is lower for me than evenings
Firstly I get faster heart rate , and irregular beats, then it settles into a slower rate but higher than normal a little but still on beats out , then eventually after 8 - 15 hours it goes back into normal. When I first started 15 years ago I would feel I would faint when it went back in , that was how I know it was back in , maybe heart stopped for a short while? but for a long time now , it just quietly goes back in and I hardly notice , but I do somehow know
My episodes have increased over the years and noe I am waiting for an appointment with cardiologist , I believe a pacemaker would be best option for me
all best Ray