hi there, drinking plenty of water has never hurt anybody expect when the doctor has asked you to restrict your water intake. The dark colour of urine could be due to high concentration or could be due to passage of pigments, blood or other sediments depending on your history of medication or any other preexisting health condition,.my suggestion would be to continue taking plenty of fluids and get a urine routine exam with a microscopy and if required urine cytology
to look for any other cause. You will need to be examined by a physician to rule out any systemic cause of this problem. Take care.