First time with Plan B

23 y/o

Hey ladies, my boyfriend and I had sex about 4 days ago, and I was on the last day of my period. He ejaculated inside and got me plan B and I took it within the hour. This is my first time with it so I'm not sure what to expect. It's been about 4 or 5 days and I'm having some spotting almost like a light period its a kind of dark brown in color... is this normal? I have PCOS if that matters

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