Took a pregnency test a week after sex came out positive, is it valid?

Pregnancy test: The at home pregnancy tests are usually very reliable but can give you "false positives", i.e. They say they're positive, but in reality it's not for a true pregnancy. You can repeat the at home pregnancy test or get a blood HCG test from your doctor. An ultrasound will also confirm pregnancy that's occurring within the uterus and not somewhere else (fallopian tubes). Hope this helps!