Severe anxiety physical symptoms. Wrong?

Hi I have been facing a lot of issues from last few years on excessive worry about my heart functioning that I'm getting real physical symptoms of irregular heartbearts, chest pressure, persists dry cough, left arm pain and numbness, persistent dizziness that I can't even walk or stand. Have gone through various test stress echo, tmt, 100 ecg etc, all says tachycardia thats it. No other issue. But i still feel that there is something wrong with my heart and as if it is going to stop. Due to all this,I'm constantly thinking about death which has created a significant impact on my mental health. I'm so anxious all the time that I can't even sit still. I'm constantly moving to fro and nothing can actually calm me down. I'm all the time tired, heart pounds, skip heart beats, constant dizzy and what not. Could you please help me with below? - can anxiety cause persistent severe dizziness and off balance feeling ? - can it cause irregular heart beats? - or is it something medically wrong?