I took my Plan B pill last week on the last day of my period. I wasn't really scared about the spotting, because I was warned it could lengthen my period. Plus it wasn't flowing that heavy. Now it's been 10 days on my period and now for the last 4 days I've just been spotting brown blood. And sometimes it's chunky, like little black specs too. Am I okay? Should I go see a doctor?