Egg Glitching

Hello Everyone,

I am getting a strange glitch. I am making a grenade plugin that when you throw an egg with the name Grenade it shoots an egg and makes an explosion where it lands. Except if I right click a block with nothing in my hand after I shoot it it shoots another egg. Why is this happening? Here is how I shoot the egg: (This is inside PlayerInteractEvent)

Code:java

        Vector v1 = e.getPlayer().getEyeLocation().getDirection().multiply(2.0);
        if (e.getPlayer().getItemInHand().getType() != Material.EGG)
            return;
        if (e.getAction() == Action.RIGHT_CLICK_AIR) {
            if (e.getPlayer().getItemInHand().getItemMeta().getDisplayName().equalsIgnoreCase(ChatColor.GREEN + "Grenade")) {
                e.setCancelled(true);
                Egg egg =e.getPlayer().getWorld().spawn(e.getPlayer().getEyeLocation().add(v1.getX(), v1.getY(), v1.getZ()), Egg.class);
                egg.setMetadata("grenade", new FixedMetadataValue(this, true));
                egg.setVelocity(v1);
                bob.add(e.getPlayer().getName());
                return;
            }
        }