Generally you ovulate 2 weeks before your period.so by having sex week before woudnt result in pregnancy.how long are your cycles im guessing if your saying that sex happen 1 week before your period,then you must have a 35 day cycle.
Victoria01 is right...the only way to tell is if you test. We can't tell you if you are or not, but I can tell you that there is a possibility.
I'm sorry, but the only way to know if you are pregnant is to take a test.