Hello there.

Thanks for writing to us.

Since you are two weeks overdue, the first possibility to be ruled out is pregnancy especially if you have history of unprotected intercourse.
Pregnancy test can be done with home kits for beta hcG in urine. Its should be positive if you are 2 weeks overdue and pregnant. A blood test for beta hcG is more specific and if negative, it rules out pregnancy. False negative report with blood test is rare.
I have read your medical history. If you are on treatment with anti depressants like fluoxetine, then they can have an impact on your menstrual cycles. They can cause delayed periods or ammenorhea(no periods). Also antidepressants can cause weight gain which inturn lead to irregular periods. So the other possibility can be side effects of the medication you are on. You can mention your treatment history to me so that I mention the possibility better.
Periods are also delayed by factors like emotional stress, anxiety and change in environment. Weight gain or weight loss can also affect menstrual cycles.
The nausea, morning sickness which you have mentioned can also occur with antidepressants.

So if this is the first time you have missed your periods, you should first rule out pregnancy.Then you can visit a gynecologist and take medication for withdrawal bleeding.
If the problem persists in subsequent cycles, then you need a proper evaluation for delayed periods with certain hormonal tests and ultrasound to rule other causes of delayed periods like ovarian cysts and pelvic inflammatory diseases.

I hope I have answered your query.
You can revert back if you have further doubts.

Take care.

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