What Causes Pain In Lower Abdomen,back And Dark Urine After Undergoing Hysterectomy?

I had a hysterectomy 3 1/2 weeks ago. It went great! The surgeon took my uterus, fallopian tubes and cervix but left my ovaries. I had 3 fibroids. I am 59 years old. I got better really fast and last week began teleworking 2 - 3 hours per day and walking a little. I visited the surgeon after 2 weeks and she was really pleased with my progress. I had no need for any pain meds after the 2nd day at home. But starting 2 days ago, I began having cramp-like pains in the lower abdomen but they d sometimes also be in my lower back. Sometimes the pain would be sharp and sometimes just crampy. Yesterday I started having urine leaks and today my urine turned a darker yellow. I will be calling my doctor Monday, but I need to know whether or not something more serious may be wrong and require urgent care.