You have probably two different repos with the same name: a local one with your package you have worked on and a remote repo which you have created on github.
You have to set the origin of your local repo. Here are the commands to do that:
git remote rm origin
git remote add origin https://github.com/PATH/TO/YOUR/REMOTE/REPO
git config master.remote origin
git config master.merge refs/heads/master
After this do
git push -f origin master
on a git command line or as proposed in your screenshot, forcing the push.