You can assume for some disease but you can't self-diagnose them especially conditions like diabetes, kidney disorders or high blood pressure. These conditions requires certain diagnostic procedures to prove them.
Diabetes requires measurement of the blood glucose level and hypertensia requires measurement of the blood pressure.
Kidney pain (colica renalis) is severe, sharp pain that irradiates from the lower back to the front and down to the genitals. It is often accompanied with often peeing. In case of kidney infection you can also have fiver. Physical examination, blood analyzes, urine analyzes and abdominal ultrasound are requested for confirming or excluding any kidney disorder.
Can you go to your GP now?