Should facebook pixel code appear in head?

I don’t understand this plugin at all. I added my pixel ID to it, checked the boxes and saved it. I looked in the source code on woocommerce pages and dont’ see the pixel code or the pixel id or anything related to facebook pixel at all. Should it appear in the page’s source code? When do events get recorded? How do I know if its’ working? I’m totally lost, I thought this would be easy. I had the pixel code on a different site, but I deleted it from there, but facebook is still indicating green meaning the pixel is active, but where?