I've the same thing. My heart wouldn't stop pounding hard. I can feel it all the time, see it on both sides of my neck when I look into a mirror. making my anxiety worse, had a panic attack recently which I never had before. It all started when I tried a new whey protein powder which actually caused my heart rate to go down a lot, like 49 bpm. Stopped it, heart rate went back to normal range 60~90 but the pounding never went away. Did an ecg and blood test, nothing's unusual, blood pressure sometimes low, never high. It's worse if I have some bloating which cause some tightness on my upper body. Sometimes I feel like there's something stuck in my chest. I'm worried that there's something wrong or that this will be forever. Anyone knows how to reduce the strong pounding?