What you require is a Next Page section break.

Headers and footers are properties of the section, not the page. When you begin a document, you have one section, which continues, with subsequent pages inheriting the same headers and footers, margins, etc., until you tell word, with a section break, to begin a new section. With your cursor at the end of the last page before your new section need, go to the Page Layout tab, use the down arrow next to Breaks, and select Next page in the Section Breaks part.

A page break is not the same as a section break; it merely forces your cursor to the next page, but does not create a new section.

Once you have inserted the section break at the end of the page preceding your last page, there is one more step before inserting your image or making any other change to your header or footer. When you activate either header or footer, you will see a tag below it on the right that says Same as previous. This is what you don't want, since any change you make will then replicated in the previous pages as well. Click on the header and footers tab that appeared above the ribbon when you entered the header/footer "layer", and deselect "Link to previous." You may now insert your image.