So, simply explaining my current situation:
- I kept pushing changes into origin master (no branches made yet)
- I decided to change the commit message of the initial commit of the Github Repository
- I did $ git rebase -i --rootand change the commit message successfully
- I tried to force push by doing - $ git push --force, but to get the following error:- fatal: The current branch master has no upstream branch. To push the current branch and set the remote as upstream, use git push --set-upstream origin master.
- I tried to follow the instruction, but to get: 
! [rejected]        master -> master (non-fast-forward) error: failed
to push some refs to 'git@github.com:BLAHBLAH.git' hint: Updates were
rejected because the tip of your current branch is behind hint: its
remote counterpart. Integrate the remote changes (e.g. hint: 'git pull
...') before pushing again. hint: See the 'Note about fast-forwards'
in 'git push --help' for details.
What am I doing wrong?
 
     
    