If you are already 17 days beyond your missed period date, and your pregnancy test is negative then it is likely that the delay is possibly caused by stress-induced hormonal imbalances during the month. The symptoms you are experiencing of bloating, increased frequency of urine and nausea headache is a part of premenstrual syndrome which in absence of pregnancy may mimic early pregnancy symptoms but indicate that the menses shall ensure in few days.
It is suggested that you may wait for next 5 days and if not resumed then get an ultrasound pelvis done and check for endometrial thickness. If the endometrial thickness is more than 10m m, then you may opt for a progestin withdrawal to resume your menses.
I hope I have answered your query in detail,
wishing you good health,
These Q&A’s are for educational purposes and should not be relied upon as a substitute for medical advice you may receive from your physician. If you have a medical emergency, please call 911. These answers do not constitute or initiate a patient/doctor relationship.