Am i wrong?

So I've seen people respond to questions about the didgital test like

Q. I took a digital test it said 1-2 weeks pregnant

R. It says 1-2 weeks since ovulation, your really 3-4 weeks

How is that possible? I thought you get pregnant when you ovulate. You definitely wouldn't if gotten pregnant before, so how would you really be farther?

Wouldn't the answer be that the test isn't going by your ovulation? That the doctors would say your 3-4 weeks because they go off of your last period?