I Got This Pimple Like 2 Days Ago On My

I got this pimple like 2 days ago on my butt it's painful so I tried popping it now I think it's a boil cause it's red and swollen about the size of quarter if no a little bigger than that and now it has a black dot. I want to know if there's any at home treatment I can do? I know not to pop it any more cause it could get in my blood stream. I've been cleaning it and putting antibiotic cream on it .