hi i have a question...im kinda concerend,about a year and a half i was sitting down and my heart beat really hard then it started beating really fast. i got scared so i went to the doctor they told me i had an axiety attack,and i went with it.But ever since then my haret would do that every now and then.i thought it was heat attach symptoms.but i fell fine,i play bball,im about 6 foot ,150 pounds,and im only 16teen. Please help thanks