Was I hacked...?
If your password was changed and your characters were stripped then you got hacked. The error code may be s separate problem.
You need to scan your computer and also check for a keylogger. Once you are sure your computer is clean, then change the password again. If you had a keylogger, change your email password also. Then contact support about an Account Resoration, a rollback to a point before the hack. Top of page-Support, then top of page-Submit a request.
If you have a smart phone, you might want to change your email password and enable mobile authentication if your email has it via that.
ArenaNet Communications Manager
By all means contact Support so the team can help you with this.
Gaile Gray
Communications Manager
Guild & Fansite Relations; In-Game Events
ArenaNet
Communications Manager
Guild & Fansite Relations; In-Game Events
ArenaNet