Well, to start with, you shouldn't be letting your choice of IDE dictate your code architecture. IDEs are a developmental aid (some might say a developmental crutch), so if yours is getting in your way, it's not doing its job and you should reconsider your use of it.
When you talk about using "the PHP function header()", I presume that you intend to use it to issue an HTTP redirect response. Think about what you're doing: HTTP is stateless, but you want to preserve state across page requests (the privacy page is a different resource to the contact form, as your uneasiness about not changing URIs shows you're aware). The place to do this, generally speaking, is in the session.
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Well, to start with, you shouldn't be letting your choice of IDE dictate your code architecture. IDEs are a developmental aid (some might say a developmental crutch), so if yours is getting in your way, it's not doing its job and you should reconsider your use of it.
When you talk about using "the PHP function header()", I presume that you intend to use it to issue an HTTP redirect response. Think about what you're doing: HTTP is stateless, but you want to preserve state across page requests (the privacy page is a different resource to the contact form, as your uneasiness about not changing URIs shows you're aware). The place to do this, generally speaking, is in the session.
It's not dictating the code architecture -- it's one of many factors to consider
Naturally I'm using a session variable. But the URL mismatch remains.