I'm 22 years old and in pretty good shape. For a while now (maybe years) I have been experiencing episodes where my heart will be pounding for sometimes hours at a time while i'm resting. My heart rate usually doesn't go beyind 100 bpm so i wouldn't say that it's racing, just POUNDING. During these episodes i often feel short of breath but not enough to cause too much alarm; i just have to take a series of DEEP breaths every few minutes to to feel satisfied. I also tend to feel realy dizzy and kind of black out when i stand up when this happens, but i've never fainted. That sometimes happens without me standing.
I have always been acutely aware of my heart beating, but at these times I get a really uncomfortable feeling in my chest. My heart sort of flutters or skips beats sometimes.
I was just wondering if anyone else has experienced similar symptoms and if they are cause for alarm.
Thanks in advance