Heart stroke?

i am a 15 yrs boy, 105 lb, and i have like a similiar problem like heart stroke. If i sit for a long time with out getting up my heart start to hurt everytime i breath, and it seem the only method to stop it is running around my house 10 time. By then my heart pump alot more but the hurt stop. I cant have heart disease or heart attack because i barely eat any fast food or high fat at all, and the fact that i am lean. The second question is that is it from hereditary or something else?