Hi There, I Don't Get A Very Fast Heart Beat

Hi there, i don't get a very fast heart beat but more like my blood is moving very fast around my heart, when I'm in a warm place and i go out with a shirt i get a big shaking on my legs, shoulder and head also teeth. Sometimes when I'm on bus my head shakes a bit and stops and it can start again it feels like someone punches me. Can you please explaine me something about it and sorry for my bad English