Use conditional is_page()
for loading script on specific page.
Here Is The Modified Version of Your Function:
//Load Scripts
function load_scripts(){
wp_deregister_script('jquery'); // De-register Existing jquery
wp_register_script('jquery', 'http://code.jquery.com/jquery.js', '', '', true);
wp_enqueue_script( 'jquery' );
wp_register_script('bootstrap-jquery',get_template_directory_uri().'/assets/js/bootstrap.js', array( 'jquery' ), '', true);
wp_enqueue_script( 'bootstrap-jquery' );
// register the script
wp_register_script( 'my-script', 'URL to Script' ); // by default script will load to head
// conditionally load page
if (is_page( 'Contact' )) {
wp_enqueue_script('my-script');
}
}