Fix infinite loop?

<?php $my_query = new WP_Query('category_name=technology&posts_per_page=1');
  while ($my_query->have_posts()) : $my_query->the_post();
  $do_not_duplicate = $post->ID; ?>

  <?php the_title(); ?>

<?php endwhile; ?>

 <br/>

<?php if (have_posts()) : while (have_posts()) : the_post();
 if( $post->ID == $do_not_duplicate ) continue; ?>
  <?php query_posts( array( 'category__and' => array(62,2270), 'posts_per_page' => 1, 'post__not_in' => array($do_not_duplicate) ) ); while (have_posts()) : the_post(); ?>

   <?php the_title(); ?>

   <br/>

  <?php endwhile; ?>
<?php endwhile; endif; ?>