The newer test claim that they can detect it before your body does, in less than a week in some cases. I find those claims to be a bit hopeful, I think that in 2 or 3 weeks you'd be able to trust the results
You should wait for 6 to 12 days to take a home pregnancy test. You can also go to a heath center to get tested after the same time. It is advisable to see your doctor before you plan on becoming pregnant.