Blackheads during/after Accutane?

So not only did i have nodular acne, but I also had a lot of blackheads mostly around my mouth area. My accutane course didnt really help my blackheads, and I had this one blackhead by my lip for literally the past 3 months and it wouldn't go away, so yesterday I tried popping it. And it wasn't coming out.. and now I have a scab on my lip and it still looks like the blackhead is under there. What do I do/how do I get rid of it!?!?!