Is lots of black blood after taking a morning after pill normal?

I had unprotected sex a day or two after my period. My period hadn't been quite normal, because there wasn't the viscous black substance that usually comes near the end of it. I took a one-dose levenorgestrel pill the day I had sex. A day or two after that, the black blood came. And it kept coming for two weeks. It's been about two and a half weeks since then, my period came again but was very light and I'm not sure if the black bleeding has stopped yet. Having to wear pads for two weeks has left my vulva a bit irritated and quite a bit itchy. Especially because I had an untreated yeast infection that left my vuvla sensitive to irritation. I am 17 and cannot talk to my parents about this. If necessary, I could potentially go to Planned Parenthood with my significant other or his family.