Home pregnancy tests will not pick up the levels of HCG in your urine stream until about a week before your missed period. Sometimes you can detect them sooner. Sometimes later. The tests that the doctors do are a bit more precise and can detect the levels sooner.
It will be able to detect on 41 days. Sometimes the harmone will not set in the suitable at that time we will not able to find. On this case we can test after 45 days that will make clear test that will be pregnant or not.