I felt it right away my heartbeat in my throat and my chest. I felt the irregularity and after 30 minutes I started to feel weaker. I thought first I had a panic attack, but having had them in the past, I felt there were some differences. In my PA, something calm down after 10-15 minutes and although I can have palpitations, I don’t feel the heartbeat irregular. I have now an iWatch that can measure heartbeat and if I have a AFib episode, it will tell me. Hope this answers your question.