Blog Previous and Next links not working properly

I can’t figure out why the Previous and Next links on my blog page will not link to the correct page. The same posts come up when I click on “Older Posts”.

Under the “Reading” Setting, I have it set to 5 posts per page.

https://www.rosacreative.com/blog

This is the code on index.php:

<div class="posts">
                <?php query_posts('cat=-13'); ?>
					<?php if (have_posts()) : ?>
						<?php while (have_posts()) : the_post(); ?>
							<div <?php post_class() ?> id="post-<?php the_ID(); ?>">
                            	<div class="date"><?php the_time('M') ?><br /><?php the_time('d') ?></div>
								<h2><a href="<?php the_permalink() ?>" rel="bookmark" title="<?php the_title_attribute(); ?>"><?php the_title(); ?></a></h2>
								<small>posted in <span class="category"><?php the_category(' | ') ?></span></small>
                                <div class="post-thumb"><a class="thumb" href="<?php the_permalink() ?>"><?php the_post_thumbnail('post'); ?></a></div>
								<div class="entry"><?php the_content('…',TRUE,''); ?></div>

								<div class="postmeta more">
									<a class="standout" href="<?php the_permalink() ?>"><span>keep reading ?</span></a>?
									<?php comments_popup_link('leave a comment', '<span>1 comment</span>', '<span>% comments</span>', 'comments-link'); ?>
                                    <?php edit_post_link('Edit this entry.', '<p>', '</p>'); ?>
								</div>
							</div>

						<?php endwhile; ?>

						<div class="nav">
							<div class="alignleft prev"><?php next_posts_link('? Older Posts') ?></div>
							<div class="alignright next"><?php previous_posts_link('Newer Posts ?') ?></div>
						</div>

					<?php else : ?>
						<h2 class="pagetitle">Not Found</h2>
						<p class="center">Sorry, but you are looking for something that isn't here.</p>
						<?php get_search_form(); ?>
					<?php endif; ?>
				</div><!-- end .posts -->