Please help

My bf And i have been TTC for a couple weeks now and couple days before AF was due we took some test and got a BFN . I started having symptoms , like my boobs feel sore , i feel sick, peeing more than usual , and a little bit of cramps . I just waiting for AF and shes late 2 days so i took another test and got a BFN again? Not sure if its the brand ? Or if im just not pregnant ? Or its too early ? Please help!!!