If your username or password were wrong, it would tell you. One way to check is to go the directory where mysql is installed and type "mysql -u root -p" and if it asks for your password, the server is working. If it doesn't and gives an error like the above one, there should be a program in the bin directory thats called something like "mysqld-nt" or something with "nt" in it, just run that with "mysqld-nt install" and that will install MySQL as a service.
