In the Fills Out Form trigger, you can specify which page the form completion happened on. Click on Add Contraints and select webpage. This will allow only prospects who filled out the form on the specified page to go through the flow steps.
Thanks! So it sounds like I need a separate smart campaign for every page the form is on. I was hoping to set the trigger so that one smart campaign runs when the form is filled out, and then there would be a separate flow steps for each web page. Possible?