I want to make a admin tool available only for me when I log in as an admin and no-one else can use it (as it may cause problems) is there a way to do this?

Battleye Extended Controls (BEC). Google it.

If you're the only one with FTP access to the server, you can setup the config file so only your game ID has access to run admin commands.

You can also run most commands remotely without having to play the game.