It does seem like you didnt have your album location saved in database (looking from "guest" view).
if the above doesnt work, you may want to put some text before $this->user_location and see if the text is saved in database.
PHP Code:
function update_session() {
global $site_db;
$sql = "UPDATE ".SESSIONS_TABLE."
SET lastactivity = $this->current_time, location = '$this->user_location'
WHERE sessionhash = '$this->session_id'
AND host = '$this->user_ip'";
$site_db->query($sql);