Hello, Aspenlee,
I'm sorry, I don't know why your launcher is not working. Possibly your dad has done something which restricts access. Otherwise, hopefully, someone else will know what to do.
In the mean time, you can still play your game by bypassing the launcher. To do this, you will need to make a new desktop shortcut and link it to the correct program. This will be TS3EPx, where x it the number of the last expansion pack installed (example: TS3EP10).
Right click on the desktop and select NEW.
Select SHORTCUT.
BROWSE to locate the program named as above.
This will put a shortcut on the desktop to start your game without the launcher. (You may be able to log in once your game is running, but, I would, in your situation, choose to stay logged out. (You will not be able to earn achievement badges while logged out, but, otherwise, your game will run as normal.)