The level of hCG hormone has to be more than 25 mlU/ml for the pregnancy to be detected. If the level is lower than this, the pregnancy cannot be detected, even after implantation. Therefore, you must wait at least a week or two after missing the period to take the pregnancy test.
If you experience these signs and have a delayed period, it’s likely that you are pregnant. To get the exact results, take a home pregnancy test. It will give you accurate results. If you get negative results, wait for at least three days before you do the test again.
You can even get a blood test done to see if you are pregnant. Blood tests are more accurate than home pregnancy tests. These tests will give you accurate results as early as 6 days after ovulation.