It depends on the sensitivity of the test, i.e. the minimum amount of hCG hormone it can detect. However, for the result to be reliable, it's recommended to perform the pregnancy test once there is a missed period. This means that you should wait to take the test until there is a delay in your period with respect to the day you expected it to come. In this way, false negatives are avoided because the hormone should already be at levels detectable by the test.
Therefore, in this situation, we recommend repeating the test on the appropriate days to obtain a more reliable result.