My heart beat very fast and then i get shortness of breath and a bit dizzy. what should i do. doe this have anything to do with low hb or anemea?

Yes can be anemia: Your heart beating fast can be related to anemia and there is a simple test for that. Your heart can beat fast from exercise, and medications, or even nerves. But if it beats so fast that you get dizzy you should see a doctor and have a heart rhythm check. Sometimes this is something that can happen periodically and that can be tested with a monitor. I would suggest having this checked.