As per your history you had taken PRIMOLUT .It contains (
NORETHISTERONE) and for Postponement of menstruation 5 mg 3 times/day starting 3 days before expected onset .Side effect of the drug is
Mental depression, cholestatic jaundice, porphyria, epilepsy, migraine, headache, breast discomfort, dizziness, nausea and vomiting, changes in libido, appetite and weight,
breakthrough bleeding, changes in menstrual flow, amenorrhoea, oedema, rash, melasma or cholasma, acne, urticaria, abnormal LFTs, moodswings, insomnia, thrombotic and thromoembolic events,
optic neuritis, altered
lipid profile.So your cramping is not due to this drug.So get a ultrasound scan to ruled out pelvic abnormalities.Thanks