Palpitation and diziness. Tense life.

I am a 28 year old male. 6 ft height and 100 kilos. Since 3 months I have been having heart palpitations once in a while. 2-3 times a month. Palpitations are generally preceded by mild breathlessness. Also I feel mildly dizzy through out the day. And if I eat spicy food, I can hear my pulse on right ear. I have done ECG, ECHO 2D, blood tests like CBC TSH T4 Sugar, LFT, Kidney function, USG etc multiple times and every time the tests results have been normal. I feel helpless since all reports are fine and doctors say it's just stress. However I don't believe I am that stressed to have these symptoms. Can anyone throw some light on my condition and how it can be cured so that I can lead a normal and less tense life. Thanks.