Shipping amount is incorrect in my orders? It's charging more shipping then what I have set up?

It might be that postage charge is also enabled in your paypal account. Please log in to your paypal account and disable any shipping charges which may be enabled. Hopefully this will solve the problem.

Steps to Disable shipping in PayPal:

1) Log in to your PayPal account

2) Click on "Profile" > This is located in the "My Account" sub menu, last option.

3) Now under "Selling Preferences" click on "Shipping Calculations"

If shipping is enabled on this page you can easily disable it from here.

You can easily set up shipping charges by clicking on "Set Prices and Options" in your OPP control panel.
Now click on "Shipping" to set up shipping charges.