Add custom buttons with custom actions in Edit Post screen in WordPress?

I am creating something for a client and I have a Class that I created with a Custom Post Type called 'PuSH Feeds' and when the user adds a new post and publishes it they can then click on one of two buttons that I have in the Custom Meta Box.

One button is for 'Subscribe' and the other for 'Unsubscribe'. I am using the save_post action hook and testing if the $_POST global has that 'pushfeed-subscribe' or 'pushfeed-unsubscribe' and then do what I need to do. However for some reason I have found that once I click on the subscribe on my local machine stops the script because it says it did 100 consecutive calls etc and I end up with loads of duplicate posts with no title.

What would be the best way to avoid this and is there a better hook I can use for these special custom actions I want to activate of subscribing to a feed (which goes into another class and performs the subscribe method)?

This is the markup I have for those two buttons I mentioned with is inside the Metabox

input type="submit" class="button-secondary" name="pushfeed-subscribe" id="pushfeed-subscribe" value="Subscribe"
input type="submit" class="button-secondary" name="pushfeed-unsubscribe" id="pushfeed-unsubscribe" value="Unsubscribe"

Then I have this for the action hook:

add_action( 'save_post', array( $this, 'pushfeed_save_post_meta' ) );

The actual hook is like this:

public function pushfeed_save_post_meta( $post_id ) {

    // Bail if we're doing an auto save
    if ( defined( 'DOING_AUTOSAVE' )  DOING_AUTOSAVE ) return;

    // if our nonce isn't there, or we can't verify it, bail
    if( !isset( $_POST['pushfeed-nonce-field'] ) || !wp_verify_nonce( $_POST['pushfeed-nonce-field'], basename( __FILE__ ) ) ) return;

    // If Subsctiption ID is empty, generate a random long number and save it
    if ( empty( $_POST['pushfeed-subscription-id'] ) ) {

        $random_number = substr(number_format(time() * mt_rand(),0,'',''),0,10);
        $pushfeed_subscription_id = $random_number . $post_id;
        update_post_meta( $post_id, 'pushfeed-subscription-id', $pushfeed_subscription_id );
    }

    ...

    if ( isset( $_POST['pushfeed-subscribe'] ) || isset( $_POST['pushfeed-unsubscribe'] ) ) {

        $subscription_domain = get_post_meta($post_id, 'pushfeed-domain', true);
        $subscription_id = get_post_meta($post_id, 'pushfeed-subscription-id', true);
        $subscription_feed_url = get_post_meta($post_id, 'pushfeed-feed-url', true);
        $subscription_callback_url = $subscription_domain . '/pushfeed/' . $subscription_id;


        $sub = PuSHSubscriber::instance($subscription_domain, $subscription_id, 'PuSHSubscription', new PuSHEnvironment());

        if ( isset( $_POST['pushfeed-subscribe'] ) ) {
            $sub-subscribe($subscription_feed_url, $subscription_callback_url);
        } elseif ( isset( $_POST['pushfeed-unsubscribe'] ) ) {
            $sub-unsubscribe($subscription_feed_url, $subscription_callback_url);
        }

    }

}

I am trying to find out why is it that the post is saving multiple duplicates with no title. But above all I would like to know if there is a better action hook I can call for these two custom actions.

Update :

Hi everyone. I ended up using an Ajax request using the wordpress admin-ajax.php when clicking a button and then firing of the subscription method. Once that is done the subscription method will do a get request and if returns a 200 code then the method returns true to the Ajax.