Generally after conception, it is possible to detect pregnancy with a test strip around 7-14 days. If you have intercourse during ovulation, the sperm and egg combine to form a fertilized egg, which usually starts to implant in the womb in about six to seven days, and HCG (human chorionic gonadotropin) is released after the implantation of the fertilized egg. At this point, an elevated HCG level can be detected by a blood test, which usually indicates pregnancy. If the test is done through urine, then it may be a shorter period of time, not detectable or weakly positive, so it is recommended to wait for another week or so, and then use a pregnancy test will be more obvious. If you want to find out whether you are pregnant as early as possible, you can go to the hospital to check the blood HCG, but if you can detect it through the pregnancy test, you also need to go to the hospital to do ultrasound to determine whether it is intrauterine pregnancy.