My resting heart rate usually is between 60-80 but sometimes it goes to 106-107 suddenly and become normal when I take deep breaths it relax. Otherwise it increase with physical activity and return to normal when I sit. I have done ecg some months back then it was normal sinus rhythm and echo 5 6 years ago which was also normal. But nowadays I has cardiophobia that my heart will fail or will get attack. My lipid profile is normal and also other markers like hcrp ,lipo protein tests all are normal. How to overcome it.