Hello,
I doubt this is anything serious and should be relatively easy to diagnose. See your doctor and expain your concerns. They will check your
EKGAtrioventricular block, ekg tracing
Ecg
Exercise stress test and either order a holter monitor for you to wear while you exercise or order an exercise stress test. It is probably just increased adrenaline early into exercise but it is better to be sure. The holter will help you figure if it is an arrhythmia. If there is a murmur on heart exam, your doctor might order an echo.
If you have a history of in your family of sudden cardiac death at a young age or syncope (passing out), it is worth mentioning this to your doctor. I hope this helps.
Good luck and thanks for posting.
For me these eventually led to PAF (paroxysmal atrial fibrillation), which needed some attention (in my case, a rf ablation to toast the offending electrically active cells found in/near the atria). 5 years post ablation, I have had some recurrence of the PAF. I am now trying a very small dose of a beta blocker to blunt the adrenaline effect while not completely screwing me over regarding sprinting. It seems to work, as now it's been three months of hard workouts and games without an incident of PAF. But if it does not work, I can always undergo a second ablation, and the prognosis is quite good as the technology has come a long way these past 6 years.
Best thing for you is to see a cardio, and even better, an electrophysiologist for a learned opinion as to prognosis.
Keep on kickin'
-Arthur