Hi and welcome to HCM.
If you have taken the emergency
contraceptive within 48-72 hours of the unprotected sexual intercourse, it should work in preventing
pregnancy (provided you were not sexually active without protection after taking it). Since the pills contain high doses of hormones, these can disrupt the normal
hormonal and period pattern causing period/bleeding abnormalities and appearance of new symptoms.
Urine pregnancy test may also show negative. Wait and watch for your next periods which can be delayed. Look out for development of any other new symptoms.If pregnancy is suspected, or if you miss your periods, or if you have abnormal periods, consider visiting your doctor/gynecologist at the earliest for thorough examination (to confirm pregnancy related changes/signs in body) and blood/serum
HCG level test (to confirm/rule out pregnancy accurately).
If pregnancy gets ruled out and if you are not ready for pregnancy, but intend to remain sexually active, you should consider getting started on suitable regular birth control measures to be protected (after periods). Be regular with birth control use as instructed. Avoid having unprotected sexual contact if you are not ready for pregnancy
Regards
Dr Santosh