Do I need any other test. Other test?

2 years back suddenly one day I had heart palpitation, during heart palpitation i feel like i am going to die and had mild dizziness but i can walk and move that time. I went hospital and taken ecg its normal.. But the heart palpitation scenario repeated again and again, whenever happened this i went hospital and taken some tests. As of now i taken 7 ecg, 2 echo, 2 tmt, 2 chest xray,lipid profile, thyroid and sugar test. All the test were normal again and again. But i could not believe the reports and doctors. I doubtful myself that i had a heart problem based on the symptoms happened in body. Whatever symptoms happened in my body i only think i had a heart issue. Iam non smoker, non drinker, no family history, BP around 130/75, LDL is 130+ and total is 196. No thyroid and sugar. Whats should i do next step, can i take any other test? I living daily with heart attack fear, i can't enjoy my life. Note: I never experience any chest pain, breathing problem and unusual sweating