Have you logged on to your nochex account to see if a payment has been received?
If no payment has been received the email could be fraudulent. ie trying to get you to send an item.
I've have emails supposedly from bidpay, amazon, paypal and nochex. All were fraudulent.
Never use the links provided in the email as they can be methods for people obtaining your log in details.
Have a look at the link in the email, hover your mouse over it and you can see the true address! See the below example.