How to load mediaelement.js in theme template?

I included wp_head(); in the beginning of my header.php file. wp_footer(); was included at the end of the footer.php file.

Failure in including them led to the problem with the video player. Everything is working fine after adding wp_head(); and wp_footer();.

Thank you, birgire!

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)