Is it pierced? It could be because you are allergic to the metal. The belly button is the most vulnerable spot to be pierced.
If it is not pierced, keep it cleaned and well covered with an antibacterial ointment. If this doesn't make it clearer in 2 days go to see a doctor for a stronger medication.
If it is not pierced, keep it cleaned and well covered with an antibacterial ointment. If this doesn't make it clearer in 2 days go to see a doctor for a stronger medication.