Welcome to our Community and thanks so much for your first ever post; very sorry that you're having some issues with your billing at the moment. You should be able to check you full bill via your online account at anytime. This will give a break down of your bill and charges.
You can also compare with previous months bills to see the difference if needed. If a long term discount or credit was due to end, this would be listed on each previous bill. Your contract should also advise of any end date of any discounts and show the new package price. This can also be seen within your online account.
In regard your your missing channels; are you getting an error message on screen? Did you call to remove this package recently? We do require 30 days notice to remove the Sky Sports and Movies. (If it's just the HD channels - do you subscribe to the HD?)