I agree with the post above, wait a few mow days and test early in the morning. If that is still negative and your period doesn't show up, get your beta-HCG levels tested at your Doctor. That way you will know for sure.
Many things can cause a late or missed period. As the other poster said, wait a few days and test again with first morning urine. If it is still negative and you haven't gotten your period, see your health care provider for a blood test.
what it out a few more days if your period is still a no show take the test again if your still getting negative try going to your doc for a blood test that will for sure tell you accurate results. best of wishes