Hi, Thanks for asking the query, Swelling on the roof of my mouth is due to the infected tooth which is draining its abscess Drainage of the abscess is required followed by course of antibiotics and analgesics. I would suggest you to visit the Dentist get the clinical examination done take an x-ray of the tooth , root canal treatment is needed in the infected tooth. Maintain a good oral hygiene. Hope this helps out. Regards.