I do believe you can't use things like that. Only letters.
I think mods(or admins) can change something for you once..
If not, You have to delete and make a new one.
However i don't know all that much, So well, Lets just say i lost my marbles, And I'm sorry. D:
*Edit*
Contact a Admin or Mod about it if nobody seems to answer this. However you didnt start anything really so i suppose starting a new account wont hurt.