Hallow Dear,
One course of Primolute N would not regularize the periods, it will just get withdrawal bleeding.
All the symptoms like brown discharge, soreness in the breasts,
nausea, headache you are having could be after effects of Primolute N which is a Progestational medicine. Of course, though not
brown spotting, rest of the symptoms can be due to
pregnancy also.
Since your pregnancy test even 11 days after missed period is negative, you are not pregnant.
To me, all your symptoms appear to be due to Progestational preparation. Some salt restriction in the diet may alleviate some of these symptoms to some extent.
Now to regularize your menses, you may take some oral birth control pills for 3 cycles, with the advice of your Gynaecologist.
I hope this helps you and clarifies your doubts.
Dr. Nishikant Shrotri