Is there always a fever when you have a kidney infection. and can the infection make you feelin unusually weak with zero energy ?

No and yes: Urinary tract infections typically present with increased urination, discomfort with urination and abdominal pressure. Other symptoms can be flu - like symptoms/fatigue. If the infection ascends up the urinary tract, kidneys can become infected and cause high fever and serious illness. So in summary there can be a spectrum of disease, fever is not always present.