That is how mine looks too! Although according to my LMP, I should already be a week overdue for AF if my cycles returned to my normal 28 days postpartum (I just had my first pp AF last month) and I'm still getting those light lines. So I'm very worried about a chemical pregnancy--that is how my lines looked when I had a c.p. in 2010. :/ Best of luck to you!! Hopefully it is just very early for you and your lines will darken!