Hello dear
I understand your concern
Delayed period is most common by the pregnancy in the sexual active lady.
But it should be confirmed by the pregnancy test and or blood HCG test.
I would suggest to go for blood HCG for final confirmation of pregnancy as it is more accurate then pregnancy test.
If blood HCG will less than In absence of pregnancy delayed period could be due to hormonal imbalance,
ovarian dysfunction,
endometriosis,
thyroid disorder.
For that consult the gynecologist and undergo reproductive and thyroid hormone analysis, USG scan,
ovarian follicle study to confirm the cause.
Progesterone pill can be used to induce the period
Other treatment depend on the cause.
Avoid stress, drink plenty of water, eat health diet, do regular exercise.
Hope this may help you
Contact further if follow up needed
Best regards
Dr. Sagar