We have no idea "how" overweight you are, but any amount should be addressed to get to a healthy weight.
As for your hear rate, the numbers look good to me, they are not low. On the other hand, if you are shot of breath or dizzy then your HR is too low or the oxygen saturation level is too low (these are just guesses... you have to see a doctor to get hands-on testing), or perhaps you blood pressure is also low What is your blood pressure? Overweight usually means high blood pressure.
Get some exercise and watch you food intake, get moving toward your healthy weight, and you'll feel better even if your HR stays the same.
My bp is usually around 115/70