is my period coming soon?

so basically my period is about 3-4 days away from starting and i've been masturbating while in quarantine because there's nothing better to do but that's besides the point. everytime i finger myself there's brownish blood on my fingers? this has been happening for the past 2-3 days. does that mean my period is coming or did i just scratch myself? cause after i'll spot for about 10 minutes and stop?