Thank you for writing!
We can't say what is going on but a sign of Diabetes can be dark urine with sediment. This is due to glucose or ketones being released into your urine. Are you having any other symptoms like fatigue or excessive thirst? Or blurry vision, numbness or tingling?
Even if you are not experiencing any other symptoms, it's a good idea to have a urine sample checked. Call your doctor to schedule. It may not be diabetes at all, it could be something else or dehydration early in the morning but it's best to check.