[git] Why am I getting the message, "fatal: This operation must be run in a work tree?"

Just in case what happened to me is happening to somebody else, I need to say this:
I was in my .git directory within my project when I was getting this error.
I searched and scoured for answers, but nothing worked.
All I had to do was get back to the right directory ( cd .. ).
It was kind of a face-palm moment for me.
In case there's anyone else out there as silly as me, I hope you found this answer helpful.