Hi akrasi augustina
Welcome to HealthcareMagic.
can help in changing the cycle.But more important is to know the cause of delay in periods.As you had sex in safe period , you may not be pregnant.There can be a chance of any ovarian disease
which can be confirmed by examination and ultrasound
You should visit your Gynecologist and get examined. You can take the hormone pills under Gynecologist`s prescription.