Custom user registration fields in user_register hook

I am trying to send an email to administrator with user_register action hook and wp_mail() function when a new user registers. I created some custom registration fields and I want send them via e-mail, but I cannot access them via the get_user_meta() function. I tried to debug this in front-page and using this get_user_meta() function gets me my custom fields, but in functions.php in my custom function, fields are missing and I get only few fields:

(nickname,first_name,last_name,description,rich_editing,syntax_highlighting,comment_shortcuts,admin_color,use_ssl,show_admin_bar_front,locale,wp_capabilities,wp_user_level)

add_action( 'user_register', 'so27450945_user_register', 10, 1 );
function so27450945_user_register( $user_id )
{
    $user = get_user_by( 'id', $user_id );
    $user_meta = get_user_meta( $user_id );

    $blogname = wp_specialchars_decode( get_option( 'blogname' ), ENT_QUOTES );

    $message  = sprintf( __( 'New user registration on your site %s:' ), $blogname ) . "rnrn";
    $message .= sprintf( __( 'Username: %s'), $user->user_login ) . "rnrn";
    $message .= sprintf( __( 'E-mail: %s'), $user->user_email ) . "rn";

    $message .= $user_meta['reg_company'][0];


    @wp_mail( get_option( 'admin_email' ), sprintf( __( '[%s] New User Registration' ), $blogname ), $message);
}

Custom fields created with:

// Adding Company information on account registration
function wooc_extra_company_register_fields() {?>
  <p class="form-row">
    <input type="checkbox" class="input-checkbox" name="reg_company" id="reg_company" <?php if ( ! empty( $_POST['reg_company'] ) ) echo "checked"; ?> /><?php _e( 'Registrovat velkoobchod?', 'vinabg' ); ?>
  </p>
 }
 add_action( 'woocommerce_register_form', 'wooc_extra_company_register_fields' );

And saved like:

function wooc_save_extra_register_fields( $customer_id ) {
      if ( isset( $_POST['reg_company'] ) ) {
             update_user_meta( $customer_id, 'reg_company', $_POST['reg_company'] );
      }
}
add_action( 'woocommerce_created_customer', 'wooc_save_extra_register_fields' );

Is any chance to get this working? Maybe different functions or hooks? I’d like to just notify administrator when user created new account (using WooCommerce if that matters), and send email with all information about that user (my custom fields).