Why am I having brown discharge

I have been having brown discharge in my underwear and when I wipe. I'm not sure what causes this. Google says pregnancy could be it.. but I'm on birth control pills and I highly doubt I'm pregnant. Google also says brown discharge could be old period blood. But I've been off my period for 1.5 weeks. I also read that rough sex can cause it, and I do engage in rough sex, but last time I was active was 3 days ago. Why would I still be having that discharge? What's wrong with me? What do you all think is causing it? Is it a big deal?

its just old blood from your previous period im sure.. thats what it sounds like

i used to get a lot of brown blood when i was on the implant. i think everything just works differently when on birth control. how much discharge is there? the odd spotting isnt likely to be anything alarming. if youre concerned then see a doctor