If you were having regular periods in the past and if you are sexually active without contraception
, then the first thing to be excluded is pregnancy. You have done that. Now, the other things that can cause such a situation are sudden weight changes, stress, infections, medications, hormonal disorders, polycystic ovaries
etc. Sometimes a kickback is needed for the system when the normal pattern is disrupted and this is done by induction of menstruation
by progestogens. you will get a withdrawal bleeding 3-5 days after completion of the treatment and count that as your new date. Please remember that Norethisterone
is contraindicated if pregnancy occurs or when pregnancy is contemplated. You may also try to maintain a healthy weight, do some regular exercise and eat healthy. Stress can be relieved by meditation
and rest. Hope all your doubts are cleared. Good luck.