This isn't correct, Nitin.
Within the context of a Filled Out Form activity, the Referrer constraint is the page the form was on. It is not the page prior to that page.
You're thinking of the JS document.referrer/HTTP Referer: header. But that value indicates the page that led to the document. That is, the pageview that happened directly before the current Visit Web Page activity.
The referrer of a form fillout — like the referrer of an image or any other sub-resource on the page — is the current main document.
The correct way to identify the page an embedded form was on is to use the Referrer constraint.
I wrote about referrers at Here’s why your “Autofill from Referrer Parameter” setup stopped working.