Hello. I’m 26, physically active and healthy but I have a constant fear im about to die. I constantly think about my breathing and think im not getting enough oxygen and begin to manually breathe. I also have this constant fear I’m going to have a heart attack, to the point were if I walk at all I will think my heart rate rising will give me a heart attack. I have took myself to 2 ER’s and paid to see a private doctor for an MOT. He gave me an ECG, lunging capacity test etc and came back and said they’re perfect. So that’s 3 ecg’s I’ve done and all have been perfect and still can’t stop convincing myself I’m dying. This has caused me to suffer severely with dpdr and everything has felt unreal and like a dream. Once that kicks in, it makes me focus on my breathing again and it’s just a horrible cycle. Please does anyone have any advice?