Edit Loop Into Days & Categories

Hello all! If you could help, I’d greatly appreciate it! Currently, I have edited my loop so that it is divided into days and displays headers for each day. For example, the code output is something like:

<h2>Wednesday, July 30, 2014</h2>
<POST ONE>
<POST TWO>
<POST THREE>
<h2>Tuesday, July 29, 2014</h2>
<POST ONE>
<POST TWO>

It’s great that it’s working and the days are divided, but I also need to divide the days into sub-sections using categories. For example, something like this:

<h2>Wednesday, July 30, 2014</h2>
<h3>Columns</h3>
<POST ONE>
<h3>Links</h3>
<POST TWO>
<POST THREE>
<h2>Tuesday, July 29, 2014</h2>
<h3>Columns</h3>
<POST ONE>
<h3>Links</h3>
<POST TWO>

Currently, my loop looks like this:

<div class="blog-style">
			<?php if (have_posts()) : while (have_posts()) : the_post(); ?>
				<?php if( $current_date != get_the_date('l, F j, Y') ){
					echo '<h2 class="date-separator">'.get_the_date('l, F j, Y').'</h2>';
					$current_date = get_the_date('l, F j, Y');
				} ?>
				<?php get_template_part(THEME_LOOP."post"); ?>
			<?php $counter++; ?>
			<?php endwhile; else: ?>
				<?php get_template_part(THEME_LOOP."no","post"); ?>
			<?php endif; ?>
			<?php customized_nav_btns($paged, $wp_query->max_num_pages); ?>
		</div>