Plan B Question

I took Plan B in August at the end of it, I haven’t gotten my period yet. So it’s been about 3 weeks since I took it , I spotted lightly for 3 days which I know is normal. Then about two days ago I spotted again and it was very light not enough to wear a panty liner or anything but I had a blood clot , which I’m not familiar with when taking Plan B , I’ve been feeling not so good and I still get boob tenderness which was a side effect of the Plan B , what’s going on?