user account

Earlier today i went to a apple-store who helped me install Sierra High on my MacBook Pro (had problems with installing it). Everything installed sucessfully. They were installing Java, but i had to go, so i closed the Mac and was going to continue install it at home. When i got home, my Mac was turned off. I had to log in to either a guest account or my private account. I wrote in the password to my private account, and it started to load (looks finished). Now it has loaded almost 2 hours, and nothing happens. It doesent enters the main menu. What should i do now?