I'd recommend calling or going in to see the dentist who did the procedure. They will be able to take a look inside your mouth to make sure things are healing up as they should be and that there are no complications.
The lump can be pus building up (If your cheek/face starts swelling then it can definitely be an indication of an infection), the lump could be a blood clot that forms there during healing, or simply because of irritation to the area, which will go away. Canker sore could have formed due to the surgical stress in that area as well.
After the extraction of a wisdom tooth, there is a pretty substantial cavity made in your jaw were the tooth once was. This takes a while to fill in and heal over, during this filling process the cavity can be very delicate and sensitive. This might explain the "bump" you are seeing.
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Thanks,
Dr. Jonathan Everett