Hi, dear I have gone through your question. I can understand your concern. You may have some kidney disease. You should go for urine routine and microscopic examination as well as blood urea and serim creatinine test. Diabetes can leads to kidney disease also. However your headache has no relation with your dark urine. You should search the other cause like hypertension or congestion or some other cause. Consult your doctor and take treatment accordingly. Hope I have answered your question, if you have doubt then I will be happy to answer. Thanks for using health care magic. Wish you a very good health.