Long period after plan b.

Leslin
Backstory. I'm also on nuvaring. Had sex December 21st, condom broke but he pulled out took plan b. Got my period Jan 11 and it was normal lasted the 7 days, but I am still having some bleeding. Nothing too heavy. Mixture of dark and light and some clotting. Using regular tampon and it doesn't soak it. Just wondering if plan b can do this? I've also taken 3 pregnancy tests and they've all been negative.