Is it a cold or am I a paranoid new mom?

My little girl is 3 weeks old and has been dealing with congestion, a slight cough, and no fever. Her nose isn't runny and her cough produces no mucus. She also still has a healthy appetite and sleeps fairly sound. Her little nose sounds terrible when she breaths and I'm worried this is the beginning of something and I want to be proactive. We are running the humidifier and using saline drops to provide some comfort.

Any suggestions would be very much appreciated