you can take the test up to 5 days before your missed period but i wouldnt recommend that because its not very effective. some people have taken the first urine test and it was still too early so it was neg. then closer to your period you take another and it was positive. they also say that the first morning urine is the best but i believe that if your pregnant your pregnant. :) good luck.
if you have a good test, yes you can