With Paypal Express, the user goes to the paypal site to set the billing and shipping details, and then is returned to your site to confirm the order.
the shipping is calculated on that return to your site.
I looked at 2 items in your store:
- Adult Size Horse Mask - in this one, you have set a flat $5 shipping charge, this is working on the return to your store on the confirmation page
- 2 oz. Nasal Spray Bottle - this one is not working, for 2 reasons. 1) There is no weight set for the item. 2) in your shipping rules, you don't set a weight range that the rule applies to.
if you do not use the per product shipping charge, you need to set a weight for the product and set up the shipping rule with a weight it applies to.