Get previously visited page ID

I've done this trick like this to allow me to also check if it is one of my pages :

//Get the last page link from history

$prev_url = isset($_SERVER['HTTP_REFERER']) ? $_SERVER['HTTP_REFERER'] : null;

//Check if not null and if it contains my blog url

if( !empty( $prev_url ) || strpos( $prev_url, (string)get_blog_details()->domain ) !== false ) :
    //Then display it only if it's one of my blog page ?>
    <a href="<?php echo $prev_url; ?>" class="previous-history-link">The last page from history</a>
<?php endif; ?>

Break this down into two parts:

First, we create a variable that stores that last-visited page URL, like this:

$prev_url = isset($_SERVER['HTTP_REFERER']) ? $_SERVER['HTTP_REFERER'] : '';

Then, you could either use substr and strpos to trim down everything between ?= and the / after the ID number. like this:

$prev_url = 'http://www.yoursite.com/?p=123';
$id_block = substr($prev_url, strpos($prev_url, "?p=")+1);
$id = substr($id_block, 0, strpos($id_block, "/"));

.. Or, you could use jQuery/Javascript to achieve the same.

I haven't tested this but it should work - let me know how it does! Good luck ;)