How long until my swelling froma tooth abscess recedes?

Soon: Assuming the abscess has been adequately drained, you are being treated with the appropriate antibiotics and there has not been extension of the infection to other areas of the mouth the swelling should resolve over several days, hot packs may help. Not very different than swelling of your ankle from a sprain. Takes time to heal.

Depends: If you are taking the appropriate antibiotic and/or you have removed the source of the infection, it should resolve quickly. If not treated it will get worse until the pressure is relieved either by rupturing the abcess or it destroys enough underlying tissue that the pressure is reduced. But then it will still be there, but not hurting as much!