You are safe as long as you have not hit the submit button.
You are safe if you have typed the credentials but did not hit the submit button/link.
Although, if the form submission enabled for
left focus of the text box for password field then you are in danger.
If it sounds too complicated then just change the password to a new one. This will help:
https://passwordsgenerator.netPS: Did you report the PM? If not then report the scammer.