how long? possibly pregnant? help!!

emily
i had unprotected sex about 10 days ago (july 29th) and it was the exact day of my ovulation. i'm really ttc and i'm wondering if i can take a test and it be positive or do i have to wait two weeks exact to get a positive? also i've been having cramping and sometimes i feel nauseous late at night around the same exact time. also about 4-6 days after sex i got flu symptoms. does this mean anything? please help!!