If you are still wearing anything in your nose piercing kindly remove and keep the area clean as much as possible. It won't heal otherwise. If you have got abscess and pus in it kindly go and consult a surgeon personally for draining of your wound. Healing will fasten once your wound is drained and cleaned up.

Kindly keep the nose and the piercing clean and apply a gold nose ring or the piercing stud as they will cause the least reaction with the piercing. You may require antibiotics, antihistamine, pain killer, antacids and a topical antibiotic cream. If the condition persists or worsens visit a dermatologist