Wordpress paginate_links() not working - wordpress

Question

Using Wordpress 4.0.1
I have query set up to echo out archive posts to a page. Which works fine, here is the query.
$paged = ( get_query_var( 'paged' ) ) ? absint( get_query_var( 'paged' ) ) : 1;
$args = array(
'post_type' => 'post',
'category__in' => array($category[0]->cat_ID), // gets the category ID higher up in the code.
'posts_per_page' => 5,
'paged' => $paged
);
if ($category[0]->cat_ID == 3) {
$today = date('Ymd');
if (!empty($year) && !empty($monthnum)) {
$args['meta_query'] = array(
array(
'key' => 'event_start',
'compare' => '<',
'value' => $today
)
);
} else {
$args['meta_query'] = array(
array(
'key' => 'event_start',
'compare' => '>',
'value' => $today
)
);
}
$args['order'] = 'ASC';
$args['orderby'] = 'meta_value';
$args['meta_key'] = 'event_start';
}
$the_query = new WP_Query( array_merge($wp_query->query, $args) );
I'm getting out the posts and then at the bottom I want a pagination feature.
Here is my pagination query
$args = array(
'base' => add_query_arg( 'pagenum', '%#%' ),
'add_args' => true,
'format' => '/page/%#%',
'current' => max( 1, get_query_var('paged') ),
'total' => $wp_query->max_num_pages,
'prev_next' => true,
'prev_text' => __('« Previous'),
'next_text' => __('Next »'),
'end_size' => 3,
'type' => 'list'
);
echo paginate_links($args);
But whats happening is the link at the bottom is showing the url twice like this
http://domain.com/category/recent-seminars/page/2domain.com/category/recent-seminars/page/2/?future
This results in 'Nothing Found' (unsurprising), but even if I delete either the first half or second half, I still get nothing found.
I've tried loads of different combinations in the paginate_links query but nothing is working.
EDIT
I've amended the main query to this now
$paged = get_query_var( 'paged' ) ? absint( get_query_var( 'paged' ) ) : 1;
$args = array(
'post_type' => 'post',
'category__in' => array($category[0]->cat_ID),
'paged' => $paged
);
$today = date('Ymd');
if ($category[0]->cat_ID == 3) {
$args['meta_key'] = 'event_start';
$args['meta_query'] = array(
array(
'key' => 'event_start',
'compare' => '>=',
'value' => $today
)
);
$args['order'] = 'ASC';
$args['orderby'] = 'meta_value_num';
}
This works for the first page, but as soon as I click one of the next page links, it stops working, however If i take out the $args['meta_query'] array, the paging does work, but the posts are in the wrong order.