Back when I was going through the start of my main bout of health anxiety, I started to worry about a fast heart rate and what felt like a pause and then a big THUD beat. I got so worried about it my chest started hurting and I convinced myself I was about to die, and that evening spent five hours in A&E, just to be sent home with an appointment for a ECG. This turned up nothing, and even though to me my heartbeat pattern was terrifying it was within normal boundaries and it was all put down to anxiety.

I still get these symptoms but see them as a sign my stress levels are high and I need to slow down.