Brownish discharge? Help!

So my period ended a week ago and I had old blood still coming out for three days after. It stopped and the next day me and my boyfriend had sex and he fingered me and that night I had this really light blood that was really watery and I looked it up and it seems like my boyfriends nails could have scratched me but today we didnt do anything and I have what looks like old blood again. I havent had my period in over a week. Maybe it's not blood what does brownish discharge mean??