Hi and thanks for the query, What you describe clearly indicates it would be very appropriate for you to have a good follow up with a kidney specialist (nephrologist). It would be very important first to know if you have been previously been diagnosed as hypertensive or as being diabetic. This is important because this could explain to a very large extent the headaches experienced and loss of kidney function. A clinical evaluation, coupled with urine testing, serum electrolytes and an abdominal ultrasound for a start could be very important for the nephrologist. A urine cast and cytology and serum creatinine and protein levels with a urinalaysis are baseline exams of utmost importance in your care. Determining the actual functioning state of your kidneys, any cormobid conditions that could compromise their function are key aspects in orienting and adapting management. I strongly suggest you book an appointment with the nephrologist for further management. Thanks and best regards, Luchuo, MD.