Primary Menus not semantically correct

Hi Sakin, My blog/bio website is progressing (glacially). I am conscious of trying to get it "semantically correct" and the home page is looking okay based on this online evaluation tool (click on link & then No Styles option): http://wave.webaim.org/report#/http%3A%2F%2Fwww.robertfairhead.com%2F However, all other pages have a problem where the H3 Primary Menu appears before the H1 content title: http://wave.webaim.org/report#/http://www.robertfairhead.com/short-stories-writing-on-dogs-travel-writing-comedy/ (I made a change in functions.php of my child theme so that the content title would be an H1 instead of an H2.) It occurs to me that I need to stop the H3 tag being applied to the Menus, but I can't find where to make the code change. My question to you is two-fold: 1) Should I worry about it being semantically incorrect; & 2) If so, where can I find the code to copy into the child theme and change. Thanks, Robertf