$host = $_SERVER['SERVER_NAME'] . $_SERVER['REQUEST_URI'];
if($host === "domain.com/checkout/") {
    //if im at that page, I get a alert as I should
    echo "<script>alert('$host');</script>";
    return false;
} else {
    //Here i get the h alert only at pages that is not checkout, BUT require is loaded at checkout as well. Which it shouldn't.
    echo "<script>alert('h');</script>";
    require_once 'lazyload.php';
}