Breasts growing

I’m 17 years old, and i’ve been on birth control for almost a year. Lately I feel like my breasts have been growing, but i think it might be because of my birth control brands consistently changing at my pharmacy. (I use the pill) I’m sexually active, but my periods have always been consistent and still are, so i’m convinced i’m not pregnant. would my breasts grow just because of the hormones? or should i be worried?