getting a little nervous..

hi! im currently 17. and nervous about my period rn. the last time i had sex was 2 weeks ago exactly. (idk if this changes anything but this was the first time ive had sex in over a year and a half.) im on the birth control pill tri-lo marza and i take it everyday at the same time. i havent missed any this month or last month. my bf didn’t cum/finish at all before, during, or after we were together. but ik precum could b a tiny possibility. i was the least fertile when we did it in my cycle according to my apps. ive been really stressed recently over this situation since im on the placebo pill since last sunday. im also stressed ab other things in life rn too. but stress have never really affected my period before in my life. this past week n last week ive had my normal pms symptoms (including cramps literally this morning) but still no blood. (also idk if this tells anything or not but ive been having whiteish discharge this placebo week) im really nervous about this especially bc my parents don’t know we had sex. so what do u think the chances are? thankss