Period came early on the pill

Hey guys so it’s currently Wednesday and I’m supposed to start taking my placebo pills on Sunday. I typically get my period the Tuesday after that. I’ve been on this BCP brand for about 7 or 8 months now and haven’t yet had this problem. I had sex with my bf today and right after we were done, my period started super heavily! I’m a little nervous but hoping this is somewhat normal and that it will not happen next month! Any thoughts or suggestions would be greatly appreciated! Thanks!