User login no longer works?

I am a newbie and my son upgraded me from 10.3 to 11.1 with few problems. After one week I can no longer login with my user name. I logged into Root and reset my password without success. Next I deleted the user and added the account back in; still no luck! I’ve been reading posts without finding a cure for my problem. Any help will be greatly appreciated!

Being able to login as root gives you the opportunity to create a new user. See what happens after that! Can you login using the new user and password? If you can, is everything working normally?

I tried that but unfortunately it still would not login except as root.

Any permission related modifications to your home folder? Check in a console the permissions in /home/user and see if they are as they should (or just use as root chmod and chown).