Hello and welcome to HCM.
Thank you for your query.
The discharge of pus from the belly button could suggest the presence of an abscess
, which has started draining. Pain and a possibility of a mild fever
could be associated with this.
If the abscess has started draining it will not require any serious management, but in case it does not completely drain, it can recur. So visiting a doctor would be a good idea, a mild and short course of antibiotics, with proper sterile dressing and care for the wound should avoid a recurrence.
I hope I have succeeded in answering your questions, you could write back to me anytime for further clarifications.