What Causes Fatigue When Suffering From Diabetes And High Blood Pressure?

Hello, I am a 61 year old woman with diabetes and high blood pressure. My pulse rate has been in the low 60's or high 50's (right now it is 57). I feel like being in bed all the time and have no energy. Is this pulse rate too low. I take Proponol, Lisinopril and Amlodipine for BP and Metformin for BS. Thank you so much for your time.