Everytime i use the restroom my kidney starts hurting. is this bad?

Unclear. kidneys are: usually located (except rare congenital variations) in upper rear portion of abdominal cavity, mostly above lower edge of rib cage, so kidney pain is typically mid-back over lower rib cage, to either side of back bone. Most people, with discomfort during micturition, perceive it in lower abdomen or urethra, i.e. badder area or tube from bladder to outside. Micturition pain assoc. with infections.