A period before my doctype (on localhost) is pushing all my head meta information from <head> into <body>.
Having done some research it was suggested that it was to do with using UTF-8 with BOM instead of without, however, I have checked and double-checked (even using the W3C validator) and it's using without BOM.
Are there any other reasons this would be happening?
I don't know what the issue was in the end, but I created a new header.php, copy and pasted the content into it and everything then worked.