Late period and spotting

So I am nine days late today (grabbing a test tonight) I though it would start on Saturday because I was cramping and when I wiped after a pee there was a little streak of dry blood. Put a tampon in and three days later still no period. We use condoms correctly every time for eight months. What is the chance I am pregnant and the bit of blood was implanting? I didn't bleed my first pregnancy at all