The earliest that a urine pregnancy test can put up is at 2-3 wks pregnant. Once when i was pregnant i thought i was only 4wks but u/s showed 8weeks so i had what i thought to be a heavy normal period at 4wks pregnant (possibly a twin loss) although after 2days after the u/s i miscarried =( (due to the medication they gave me to treat bacterial vagnosis not recommended during first trimester as it causes miscarriage) i would say u would have to be 2-3wks or even 4wks ive never heard of a positive at 1 week pregnant. See a doc and ask for a u/s to confirm how far u are. Congrats and goodluck =)
I got a positive at 3w 2d. I know people that have had a period while pregnant. Try a digital test and if its still positive go to your obgyn
Try to test it again little later... Week 4/5 :D
Try another test to be sure. False positives can happen with them. And yes its possible to have a period while pregnant. If the test comes back positive, id go to the doctor to see if they can tell how far along you are.