If you run sudo with wrong password should not happen anything other than the command not being run.
HTTP request sent, awaiting response...200k OK sounds like you are running a http service with sudo maybe
wget or something, and you are getting the page, I may need more info than that.
Running sudo 3 times with the wrong password could not have changed your SU password even if you ran sudo on
sudo passwd root. Unless you forgot the password which is another question, you should try again with the same password since it is the same password as before running sudo.
To add images click the edit button bellow your question(you can find it between share and flag) and follow the instruction as in the picture:
After entering the command
wget -O - https://firstname.lastname@example.org | sudo apt-key add -
I inserted the password and pressend enter the command finishes with an OK.