My Urine Smells Like Poo, Worst Time Is My First

My urine smells like poo, worst time is my first one of the day or when I've held it in but always a smell present. my urine is dark always. I'm on medication for my back after an operation went wrong. They are : morphine, Tramadol, diaziapam. Although I've been on these for nearly a year waiting for the pain clinic it's only been like this for the last 4 months. I do get lower stomach pain and I've also just had my coil changed after 5yrs from a marina to a cooper but again I was getting this before then also. I can pin point it to when I had a urine infection for the second time within a month of each other but had antibiotics and seemed to go then not long after this started. thank you Debbie