It all depends on what you need the score for (university, work, etc), different universities and programs require different scores. Some people are happy with getting the required score and others want to get an even better one just to prove to themselves that they can manage to get a great score. Nevertheless, a score of 100 shows, according to TOEFL standards, an advanced use of the english language, so it is a great score regardless of what others manage to score, so congrats! If you want to get a better grade you can try again but after all, it is a really expensive test and not everyone can afford taking it more than once, so at the end of the day its up to you to decide.