Late period/ pregnancy?

Libby • Pregnant with my 1st!!😍❤️
My period is 3 days late, I took a pregnancy test yesterday and it came up negative, (even made my pregnant bestfriend take a test to see if they worked). 
There is a chance I still may be pregnant yeah? Like I could be like 1 week or something? 
I'm reallllyyyyy confused and stressed out, I'm 17, and a baby is not going to work right now and I would never forgive myself if I had an abortion.
What should I do? :/