Showing a message (perhaps using a redirect) after a Fileds form is submitted in Drupal 7
You can setup Rules to display a message when ever a node of the specific type is created. There is an interface for creating Rules you want

Event: Creating a new node
Condition: The node is of the chosen type
Action: Display a message

Alternatively you can use code with hook_form_alter, and add a submit handler to the node submit of the specific type, where you use drupal_set_message to display the message. This can be done faster (if you know how to create modules for drupal, and it requires less resources (is faster in execution) than the Rules solution.