Concerning the first blood test you made, could it be possible that the test was done too early, and for that reason it got a negative result?
I was unfortunately sad to read the follow-up of @gentleshaid's comment. Lack of responsibilities apparently, which is not surprising if they are as young as I could guess from your blog...
Cheers, and thanks for this very nice and instructive blog!
RE: Are pregnancy test strips good enough to confirm pregnancy status