Hello dear
I understand your concern
Delayed period by 3 week is not norma.
If you have sexual intercourse in the fertile phase of cycle then pregnancy is most common cause of the delayed period.
You did not mention when did you go for the test.
Pregnancy test will give positive result 10 days after delayed period.
Now I advise you to go for accurate test to confirm the pregnancy like Blood HCG and USG.
If blood HCG and USG will be negative for pregnancy then pregnancy is not there.
Other cause of the delayed period like hormonal imbalance, excessive stress,
ovarian cyst /PCOS,
endometriosis, thyroid abnormality and
adenomyosis should rule out by contusing the gynecologist after proper investigations:
Reproductive and thyroid hormone analysis,
Ovarian follicle study.
In absence of pregnancy, period can be induced by giving
progesterone shot /pill.
Hope this may help you
Contact HCM for further health query
Best regards
Dr.Sagar