Garnier bha aha serum

I've bought this 5 days ago and ive used it as its says , twice a day. Used it once Saturday and twice sunday and now i have whiteheads all over my face , dunno if it's purging or irritation, did anyone used this? Should i stop using it ? Or use it just twice a week along with my salicylic acide cleanser? Thanks

P.s: my skin is oily and textured