so slow to open pages and emails even though i have 500mb broadband

[nev11]

Having left bt for a cheaper price , i believe ive made a huge mistake..Having only been with sky broadband for 2 months and getting what looks like good speeds normally a test shows between 200mb and 300mb but im guessing that theres huge limits on bandwith , as i just cant open anything quickly..

I have my sky tv connect direct to the hub with a cat 6 cable and youtube still buffers..

has anyone else got similar issues and feel like its not worth the money