Hello mate, I don't think making a change of username doesn't matter in this forum because whatever you choose to bear as a username, nobody will ask you that your username does not deserve here. Accept if you create an account with a similar username, like now if the username already exists in this forum.
 
Because I had encountered the same problem with my first account. my username was similar to others user, and I asked questions about it either I could change it, and many members here advised that I should not stress myself out about changing my name. The only person who can modify it for me is the forum administrator, and it takes a while to be change. So my advice to you, mate, is that if you don't like your current username, just go and create a new account since you haven't gone far; the earlier is better.