Thanks for asking the query,
According to your clinical history i suppose that you have developed infection in your canine tooth
and there is collection of abscess
in the surrounding structure tissue leading to the formation of lump.
There can be a chance of excessive wear in the enamel surface when you were wearing the braces.
I would suggest you to visit the Dentist
and get the thorough clinical examination done take an x-ray of the tooth, Drainage
of the abscess is required.
Go for complete mouth scaling and polishing.
Take a course of antibiotics and analgesics.
If the tooth is restorable can filled with a tooth coloured filling material or if the infection is deep Root canal Treatment
can be performed followed by prosthetic crown placemant.
Hope this helps out.