Baby belly button- 6 weeks old

My baby’s cord fell off when he was 2 weeks old. It healed really well (doctor said). 5 days ago we went to his doctor and they said his inside belly button was wet so they dried it and gave some medicine on it. They said no baths for a few days so we haven’t given him one yet.

Tonight, I noticed this in his belly button. What should I do? Should I call his pediatrician tomorrow ?