I got what i think is my period tuesday, 4 days before my expected period. Normally my flow is mild to heavy, and last 4 days. For the last 3 days, its been light and brown, today, i ve noticed only drops of blood when using the bathroom. Could this be implantation bleeding, taking into consideration i had sex during my ovulation time. I am 20, 98 pounds and this has never happened to me before.