Has it been brownish since it started, or was it like a normal
period at first, but is now
brownish? Are you on birth control? Birth control can cause this to happen.
A brown discharge is old blood, so it's not fresh bleeding. Brown discharge can occur at the start or end of a period, and it's just your body's way of flushing out what was left in there from your period. Sometimes, this can be the sign of STDs or bacterial infection as well.