I have sign up form for people to request a printed catalog. Right now I have it setup where they enter a list, and flow where I send an email notification to myself with their address details, and they get an email confirming we received their request. However with this set up, they can only enter the list once, if they fill out the form again in the future I won’t get a notification and know they have requested another catalog. I would like people to be able to request a catalog more than once. I have a couple of questions how to do this:

1. If I understand correctly, this can only be achieve by a metric trigged flow. Would it be correct to set up a new flow using the metric “form submitted by profile”, and use a trigger filter where the FORM ID equals the form ID for my catalog request form? (I have other additional forms on my website, like an email sign-up form). I want this flow to be only for people who complete the catalog request form. 
2. What is the difference between the “form submitted by profile” and “form completed by profile” metrics? Which is correct to use in this situation? When I view profiles in my who are in my current catalog request list, some show both the “form completed by profile” and “form submitted by profile” metrics, and some show just the “form submitted by profile” metric.