I didn't get a positive urine or blood test until I was 20 weeks along! I tried multiple urine test throughout those 5 months and got a blood test at about 4 months along, all negatives! I finally decided one more urine test and I would give up, it came out negative and then at 5 minutes there was a very very very faint line, you could barely see it! Went to the clinic and they took a pregnancy test and felt my stomach, told me I was about 4 weeks along, they then did a vaginal exam and told me I was about 8 weeks along. I had a u/s the next day to find out I was 20 weeks and 4 days a long with a girl!!
With my 2nd, they all came out negative but I knew I was pregnant! The OB that I had with my daughter did a scan and I was 6 weeks along.
I got a

at 3 weeks with my current pregnancy!
Just saw that you got your BFPs!!! Congratulations!