If it's atrial fibrillation, which is the most common irregular heartbeat, you can learn more about it here: http://www.StopAfib.org
You'll find causes and triggers, risk factors, why it can be a problem, and how it's treated.
While atrial fibrillation isn't as common in younger folks like yourself, those who "over-exercise" can be more vulnerable to it. In addition, it often runs in families, and younger folks who have it may have other family members who have had it.
Good luck.
Mellanie True Hills
Atrial fibrillation survivor & founder of StopAfib.org patient resource
m 31 about 4 years ago i had a asthma attack and then on came these irregular beats had stress test and all they said they cnt find no reason but latly they seem to get worse with short breaths, light headed, chest pain..just over all feelin yukie. they still tell me its no problem they can find but why is it gettin worse then?