Odorless discharge-baby's belly button.

My baby girl is 4 months old now. On Feb 26th, she was 3 months old that time, had some pus like odourless discharge in her belly button snd it was swollen a bit. Paed said it is just an ordinary infection and prescribed an antibiotic ointment to apply in it. He instructed us to bath her everyday. We did n applied ointment and within 1 or 2 days she was fine. Again on March 28th that discharge was present but belly button not swollen. Applied ointment and it was fine. Today I noticed this(see in pic) and suspected this to be the reason for discharge and within next few hours it broke somehow n mild discharge was there.. no swelling too.. is this a normal yeast infection or something? Or should I consult Paed again?? Please advise me on this.. Thanks in advance.