LIFE brand pregnancy tests...

So yesterday I bought the cheapest pregnancy test I could find since I'm broke til payday and needed to know asap if I'm pregnant. I tested negative, but just have this weird feeling that I am pregnant. I haven't had a period since August 27, my stomach has the weirdest bloat that won't go away, my tits have been killing me and just some other symptoms. Im going to go to the doctors if this continues but it takes awhile to get in to see one where I live, so would like an opinion or input first. Has anyone had any experience with LIFE brand pregnancy tests? How often are (any) pregnancy tests wrong?