my newborn had a slight cold

My newborn (9 days exactly) has a stuffy nose and is coughing very slightly though. I'm so nervous and can't seem to stop thinking about the worst case scenario. I feel so bad and just want to cry. I've breast fed in the hospital and made the switch to pumping and formula when I got home. I feel so bad and feel it's my fault. Going to see his pedicatrican today but I know there nothing they can do for a newborn.