I am trying to push my app to heroku and I get the following message:
$ heroku create
Creating electric-meadow-15..... done
Created http://electric-meadow-1
I was getting the second error you posted "failed to push some refs to 'git@heroku.com:floating-stone-94.git' " (with a different app name) and i got rid of it by doing the following:
git remote rm heroku
heroku create
you should see a line that says 'Git remote heroku added'. Also
git remote -v
should now have the correct app.