How long did your implantation bleeding last?

I had it with my last pregnancy only for 2 days, it was just brown streaks in my underwear. But for the last 3 or 4 days, I've been having light discharge that's mostly brown and sometimes light pink. I've been having period like cramps too which makes me think I'm probably just spotting before my period. Its due on the 5th and I ovulated between the 19th-23rd. Would it be too late in my cycle to have implantation bleeding? Does this even sound like implantation bleeding? I took a test yesterday and it was negative.