Running terminal in Mac OS X Yosemite.

Followed the installation instructions and restarted terminal:
curl https://raw.githubusercontent.com/creationix/nvm/v0.18.0/install.sh | bash

When using nvm I always get -bash: nvm: command not found

When installing again:
=> nvm is already installed in /Users/Tony/.nvm, trying to update
=> HEAD is now at 5f5eb47... v0.18.0

I do have npm already installed. Does that matter?