Morning is the best time to check.
Sometimes test systems give erroneous results, which depends on compliance with the conditions and terms of storage, the rules for conducting research, etc. It is better to give preference to tests from reputable manufacturers, rather than suspiciously cheap strip strips. The second strip on the pregnancy test can turn out to be mild precisely if the instructions are not followed. The most informative is the first morning urine, which must be collected in sterile dishes or simply substitute the device under the stream of urine.
Tests with a high threshold of sensitivity determine the interesting position most reliably. These include products under the brand Frautest, Home Test Express, BB, etc. You need to look for sensitivity indicators of 10-15 mIU / ml on the package. It is these tests that will be the most sensitive, will be able to detect hCG even before the delay and will not show a weak second strip. In terms of convenience, inkjet express systems are considered the simplest. Such tests are highly accurate, and the probability of an unreliable result is practically absent.