Under TTC, Vaginal bleeding

Dear Friends,

We are ttc from past 3-4 months,i was diagnosed with thyroid last month and the doctor has advised me to take eltroxin and i am also dieting and exercising daily.My gynaec prescribed me to take OVACARE capsules for 15 days from 5th day of my periods (last period was on 18th august) and asked us to ttc. today is the 23rd day of my cycle and i noticed brown and red spotting whenever i went to the washroom, but that lasted only for few hours. It has now completely stopped.Can you please help me out with this. Is this bleeding, the beginning of my menses or something else.I am worried and confused.