This could be a scam email (phishing scam to be precise) from a website posing as Amazon and trying to get you to log in to their website so that you give away your credentials.... and then they will be able to use your credit card details for their purchases.
Don't click any links in that email.
Don't enter a password or user name.
Instead go to Amazon.co.uk by yourself and check your account activity. Is an order there being dispatched to you? Probably not. And you probably won't get anything in the post either.
Feel free to forward the email to me if you want me to have a look at it, I would check what links are supplied and mail origin (use private message option). If you like.