Period problems

Okay, I have post my post from earlier. me and my fiancé had sex a day before my fertile window started. We done it again a day before my peak hit. Well according to glow my next period was on the 14th of october but usually do sent come till around the 16th... but I still have not had a period and my pregnancy test came back negative. I took one on the 13th and like on the 16th.. any help or advice?