Last week I noticed that my urine was dark (brownish)

Patient: Last week I noticed that my urine was dark (brownish) but it only happened wiyh my first urine of the day so i thought it was ok. Since then it seems like everytime i urinate i get strong pain in my back on bith sides. Today again i just urinated and it was brownish. I dont know if this matters or not but Ive also been having dark stools (though I did take some pepto bismal so I blamed it on that). I also have been having bruising appearing on me and i dont remeber hitting my arms and legs on anything. Should I be worried?

Symptoms: Dark urine, pain in back

Doctor: