Pregnancy Scare😱😰😨

I HAD SEX 3 WEEKS BEFORE MY FERTILITY WINDOW and I am scared that I am pregnant, but I looked up how long can a sperm live inside of you I got 5 days or 3 days and I said okay left it alone for like 2 weeks then the thought came towards me and I got stressed again then I started to have pregnancy symptoms then I realized that period symptoms are the same as pregnancy symptoms so the thing is any girl that had kids can you share something's you went through during early pregnancy P.S no morning sicknesses and I thought I missed my period but it say this Sunday it would come but I have doubts😨😰😱😫