digital pregnancy tests... some help please x

I took a digital test 6 days ago and it said
1-2 weeks. Which worked out roughly correct from what I thought. I thought 4weeks and 1 day so not majorly out but I just did another one this morning with second urine and it's still saying 1-2 weeks. 
Which given how a baby is made lol it's impossible. I had worked out that I am 5 weeks tomorrow. Someone said maybe I ovulated later than thought but that can't be the case as last weeks test said 1-2. 
Confused!?!?!?! 
I am waiting for a doc to call me but am impatient and wanted some advise. 
Thanks :)