Okay , According to this app i have on my phone , i ovulated on the 19th of march , me and my boifriend had unprotected sex on the 14th , 15th , 16th and 18th . Which Is In My "Fertile Window" . On The 19th i Threw Up , Had Bad Cramps And I Started Spotting Brown Up Until Today Which Is 4/3 .. According To The App My Cycle Should Have Began On 4/2 . I Didnt Get A Heavy Flow Until Today , i Took A Home Pregnacy Test And It Was Negative ... Can Anyone Please Tell Me What That Maybe ??