Blood tests can detect the presence of hcg (the pregnancy hormone) before urine tests.

I believe that they can give you a positive result sooner than urine because it is in detectable levels in your blood before it hits your urine.
This means, that you could take a home pregnancy test and get a negative result, but take a blood test and get a positive result. Basically, because you took the urine test too early.

Does this make sense?

Hi I took the blood test like 2 weeks ago and it came out negative but my periods wernt due yet for 2weeks now I havent goten my periods for 37 days should I take a home p test............... I dont now what to do?

It won't hurt to take a test. It's possible that something else could be going on, but, it might be a good place too start.

Hi I took the test today morning it came out negative im so relivead. I gues im not pregnant and my periods are just late or sumthing. Maybe the blood that I thought was early and lasted for a day was my periods. I was really scared that I was but im not

Hello I read your concern and i'm a ob nurse so hopefully this will
be some help to you if you can figure out when conception took
place a blood pregnancy test usually detects hcg the pregnancy hormone
just 10 days after conception

Negative tests can be wrong while positive tests are very rarely wrong, so if you have had a negative test but aren't convinced try another test.
If your blood test was 2 weeks ago and you are only due now - your test was around the time of ovulation/fertilisation and likely to be too early to detect the hcg hormone, so I would request another test now.