Custom login form code causing errors

Hi!

One of our prior developers used this code in our functions file for our custom login form redirects

// Redirect user in case failed auth from login page
add_action( 'wp_login_failed', 'my_front_end_login_fail' ); // hook failed login

function my_front_end_login_fail( $username ) {
$referrer = $_SERVER['HTTP_REFERER']; // where did the post submission come from?
// if there’s a valid referrer, and it’s not the default log-in screen
if ( !empty($referrer) && !strstr($referrer,'wp-login') && !strstr($referrer,'wp-admin') ) {
if ( !strstr($referrer,'?login=failed') ) { // make sure we don’t append twice
wp_redirect( $referrer . '?login=failed' ); // let’s append some information (login=failed) to the URL for the theme to use
} else {
wp_redirect( $referrer );
}
exit;
}
}

global $wp_version;
if ( version_compare( $wp_version, '3.0', '>=' ) ) :
	add_theme_support( 'automatic-feed-links' );
else :
	automatic_feed_links();
endif; 

// Redirect user in case failed auth from login page
add_action( 'authenticate', 'my_custom_function');
function my_custom_function(){
$referrer = $_SERVER['HTTP_REFERER'];
if ( strstr($referrer,'login') && $user==null ) {
if ( !strstr($referrer,'?login=nodata') ) {
wp_redirect( $referrer . '?login=nodata' );
} else {
wp_redirect( $referrer );
}
} }

Problem is the function titled my_custom_function is causing users who click on the request new password link to hit an error page after submitting their email address. It says too many redirects and the address it’s going too is http://our-website-here.com/wp-login.php?action=lostpassword?login=nodata

When I remove that code it’s successful and redirects to here http://our-website-here.com/wp-login.php?checkemail=confirm

Any ideas how I could keep whatever necessary functionality is there but change the coding so we don’t get the errors?

Thanks