Spotting

I starting spotting 5 days before my period was supposed at first when I went to the restroom when I whipped it was dark brown blood so I was like ok I guess am implant bleed then after that for 2 days I was spotting very light you only notice it when I whipped so when my period was supposed to come it didn't so I took a pregnancy test and negative. My period is 9days late I took another pregnancy test 3 days ago and it's negative can anyone help me? Am so confused could that have been my period?