I have PCOD problem and I am in medication to regulize past 15 days and I was met with my husband on 12, 13 & 14 days after last period. I spotted bleeding in the brown colour, but my next mensuration period will be after 10 days. I suspected I am conceving, so I did HPT and the result is -ve. Can you tell me what may be the causes and what are the next steps to be taken.