Hi there...I can understand your concern. The dark yellow colored urine could just be due to lack of intake of water. You need to consume atleast 3 to 4 lites of water everyday. Sometimes it can also point towards jaundice or other hepatic/renal disorder. Without clinical examination and few blood tests it is very difficult to tell. Start having plenty of fluids (3-4L of water per day). If you are still getting dark yellow urine after that, then kindly consult a general physician for further evaluation.