Q: Do headers need end punctuation?

No. No end punctuation is needed for the header, which is the title of the paper written at the top, (or ‘head’) of each page. Note: Some people refer to the title as the header or heading. But even then, no end punctuation is needed. You can find out more through this article that works you through to a paper title (along with the abstract and keywords): How to write an effective title and abstract and choose appropriate keywords