Pre seed

Well my fiance are using pre seed to get pregnant my bestie said that she got pregnant off it the first time she used it. It's only been a couple days she says to keep using it until the 5th and take a test then and find out if not keep going til I am. She thinks I am already but idk this pre seed is new to me I'm hoping and praying it works.. My biggest thing is trying to figure out how to keep my stress level down when I am extremely easy to upset :(