Can I cancel my order now and get a refund straight away so I can go to the shops and purchase?

Payment is taken at the time the order is placed. If you then cancel,

Card Payment  - the money should be released back to your available balance in a few days. A standard refund should take 2 - 5 days to go back into your account. We are unable to speed up this process

PayPal Payment -  funds should appear in your account almost immediately. PayPal will email you to confirm