Hello and hope you are doing well.
Please have yourself evaluated for hepatitis, this could be the commonest cause for jaundice and dark colored urine. This is more so if you have nausea/vomiting and abdominal pain. Have a hepatitis panel done. Also, sometimes increased hemolysis could also cause jaundice and dark colored urine. Blood counts and a smear can help diagnose this. Please discuss this with your doctor am sure he will provide further assistance.
Hope this helped and do keep us posted.
Hemolytic-uremic syndrome fits with all three. in that case it would be pre-hepatic jaundice, means there's nothing wrong in the liver, so far. In that case they won't find bilirubin in the urine.
both jaundice and hemolytic anemia can give dark color to the urine.
you should check hemoglobin and platelets, do urine test with urine culture. complete blood count and ESR. liver enzymes and liver function tests. Creatinine levels.
integrate water and salt to compensate diarrhea, also yogurt with probiotics.