missed my withdrawal bleed?

sooo i’ve been on the pill for 3 months now (going on my fourth) and every month i’ve been sexually active with my boyfriend and sometimes used condoms sometimes didn’t and still each month I got my withdrawal bleed. it’s friday now and I started my sugar pills sunday and I still haven’t gotten my period.... I did have sex this month but we used condoms every time this time. also I’ve never missed/been late with a pill. what should I do? should I be worried?

I guess it is also worth mentioning that when I went to pick up my refill they gave me a different brand of pill but I made sure my old brand and my new brand both had the same amount of hormones and had the same hormones in it.