What if the punching bag in your throat is swollen?

Probably infection: That is your uvula. This can get infected. You should see an oral surgeon, dentist or your physician for an antibiotic.

Uvulitis: This is either from trauma or infection. It usually occurs in the context of pharyngitis, rarely is it the sole affected region. If it does not pass, as would a typical viral infection, then have it looked at.