J.K.
Purple spots, blood blisters at the tooth site: we've more then hade both in my 3 boys :) Ther fact that they are swollen and symeterical make me believe that they are just ghis teeth moving down. Give him some thing to chew on if he will take it, or try *frozen* yogurt tubes with supervision. They might get even more purple and swell ast eh tooth decends into the gum more fully and prepares to erupt. Congrats on 2 more teeth ready to rock into place :)