unable to edit menu

I have never had this problem before until last night when I was trying to update my menu. I am able to get to the menu settings in my WordPress dashboard, but when I try to click on anything other than the “pages” box, I am unable to do so, therefore I can’t add new links to my menu other than pages. When I try to click on other sections like “Links” or “Categories”, nothing happens.

I have tried de-activating certain plugins which I thought were causing the problem, but the problem still exists. Any ideas?