Referer question

I am trying to get the referer of a page using  :  referer = request.getHeader("Referer"); 

This works fine.

The only case it doesn't work is when I open a new page from the CRX repository inside "content/mypage". I am expecting a null referer in this case, but it defaults referer of my page as : http://localhost:4502/crx/../mypage.jsp.