Hello,
First of all, you need to undergo one
blood test for beta HCG along with USG lower abdomen at the earliest to confirm intrauterine
pregnancy. Light brown discharge with late period may indicate early sign of
miscarriage. Early pregnancy test may give false negative result.
In exclusion of pregnancy, other reasons for late period with spotting in this context are
hormonal imbalance, stress/ anxiety, thyroid problem, wt gain/extreme loss, irregular eating habits, psychological factor etc.
Then, you may require some investigations to rule out underlying pathology through USG scan, thyroid profile & other hormone assay, blood sugar etc. Consult with your gynecologist and take suggestive measures.
Avoid stress / anxiety, take healthy diet with vitamin &
iron supplements, eat more fruits & vegetables , drink plenty water or juice and maintain genital hygiene properly. For breast discomfort, you can wear tight support.
If you need further consultation with me, then you can visit http://www.healthcaremagic.com/doctors/dr-soumen-patra/63326.
Take care yourself.