Hello dear
I understand your concern
If you had unprotected sexual intercourse then there is chance of pregnancy.
Following are the tests for pregnancy.
Blood HCG test: It will give positive result earliest, just 10 days sfter sexula intercourse.
Home pregnancy kit: It will give positive result 8-10 days after the delayed period.
So you can consult the gynecologist and go for blood HCG test.
Other cause of delayed period like
ovarian cyst /PCOS,
endometriosis, hormonal imbalance,
thyroid dysfunction, excessive stress,and adenomyosis should be rule out after proper investigations as follows:
USG scan,
ovarian follicle study, reproductive and thyroid hormone analysis.
Treatment will depend on specific cause.
In absence of pregnancy, period can be induced by
progesterone pill/Shot.
Hope this may help you
Contact HCM for further health query
Best regards
Dr. Sagar