Add widget to header of page

Hi. I am currently using the Spun theme for my food blog (whiskedaway.co), and I would like to add an instagram plugin to the header of my main page.

I saw a blog (Peace Love Shea),where she has a header of her recent instagram posts. That is what I’m trying to do.

I’ve looked up widgetizing my theme, but the example was for a sidebar, not a header. If anyone could help I would really appreciate it!