My dream job in to be an interpreter (portuguese x japanese, not necessarily 同時通訳) and translation would also be an option of course.

I was talking with my teacher about that today and she mentioned that there are a few good schools in tokyo and that If I'm good at it I will get a good paid job.

Supposing that there are no master courses in interpretation/translation of portuguese-japanese, do you know of any good schools?

You might find these websites useful
http://interpreters.free.fr/ Resources for interpreting
http://interpreters.freeforums.org/ There's a section in the forum about interpreting schools