Usually spotting is not a sign of pregnancy. Spotting can indicate any vaginal bleeding, including but not limited to menstruation. Spotting can be due to many different factors (hormonal, infections, tumors…) but is not generally attributed to pregnancy. If you are already pregnant, spotting could be a sign of possible miscarriage. You can take a home pregnancy test now and another one if and when you miss your next period. You may also wish to see a gynecologist to diagnose possible causes for the light pink spotting.