I used to have this problem once, for me it happened because I used the wrong encoding. I also had the right sourcecode but it came out all wrong on the actual page.
Try setting your editors settings to “UTF-8 without BOM” because the BOM is what seems to be causing that error.
Sometimes it also happens if you copy and paste text from somewhere and it copies some invisible characters. Try typing the stuff yourself, and it might just work.
(there’s more people with the same problem, e.g.
https://stackoverflow.com/questions/17566119/why-are-tag-title-meta-tag-going-from-head-to-body-tag-automatically
https://stackoverflow.com/questions/14646223/header-appearing-in-body-tag-wordpress
and what I said above usually worked for them to fix it)