Hi @FutureIvy513,
I was in a situation exactly like yours (BC in 9th, and then advanced math courses outside of high school). What I can say is that colleges view outside math courses as just as rigorous as high school math courses, provided you take them through a community college/university/certified online provider with grades. If you are concurrently taking an advanced math course outside of school as well as AP Stats in 11th grade, this will in no way reflect negatively on you. AP Stats will just seem like an elective, and your more rigorous, advanced math course will be treated as your main math course.
That being said, make certain that your outside math courses are (preferably) from an accredited degree-granting institution or an online platform that provides grades, so you can self-report these courses when applying to college and have official transcripts sent as well.
Feel free to PM me if you want to connect for more info.