Hi Doctor, Its My Third Month And I Still Did

Hi Doctor, its my third month and I still did not get periods. I have consulted a Dr and she prescribed me to take Meprate for 5 days each. But its been 2 weeks after taking that medicine I still did not have periods. I have done all my blood tests thyroid, diabetes, and all other tests are normal and my ultrasound reports are also normal. Earlier 5 to 6 months back I had the same problem but I took sysron n and periods were normal after that and there was an endometrial thickness earlier but this time ultrasound report is normal. I have two kids and I am 32 years old. My family is complete. I am so upset with this problem. Please help! Thanks