Hello, Thanks for letting us know your health concern. It is too early to detect pregnancy through the home pregnancy test for the recent sexual act. You have to go for the blood test as it is more sensitive and specific. If you have always had regular monthly cycles and had a missed period during the previous month, I would suggest a trans-vaginal sonogram in addition to the pregnancy test to know the status of the pelvic organs. If pregnancy is excluded, hormone imbalance is the possible cause. Withdrawal bleeding can then be induced using hormones. Hope your query has been clarified. Take care.