I am a type 1 insulin dependant diabetic and every time i cut the lawn i sweat profusely and my heart beats quickly! is thar normal?

Hyperhidrosis: The first thing you should do is make sure your blood sugars are not dropping too low. Certainly the physical exertion of mowing the lawn can contribute to hypoglycemia. I would also consider having a cardiac stress test and CT calcium score. You could have undiagnosed heart disease showing with the sweating and fast heart beating. Your heart could also be having rhythm issues.