Sounds like an environment issue. Your computer needs to know where to look for programmes when you run them. If you moved things around during install, it is possible that your computer isn’t looking in the right place.
To see whether my assumption is correct, first check if /users/me/.npm-global/bin
is in your path.
echo $PATH
If it isn’t there, you will need to add it to the path. Open up ~/.bash_profile then add the following line to the bottom:
# NPM global installs
export PATH=$PATH:~/.npm-global/bin
Finally, back in the shell, type:
source ~/.bash_profile
Hopefully that will have fixed your problem