Receiving an email confirmation for a transaction you did not make is a very common scam. The $49.99 amount is chosen because it is large enough to get your attention while remaining small enough to be believable.
If your account had actually been charged for a purchase you did not authorize, please refer to Get help with an item purchased from the iTunes Store, App Store, Mac App Store, or iBooks Store - Apple Support. To review or cancel charges for recurring subscriptions, read View, change, or cancel your subscriptions - Apple Support.
Excerpted from Effective defenses against malware and other threats:
Don't open email attachments from email addresses that you do not recognize, or click links contained in an email:
- A variant of the same scam takes the form of an emailed receipt for an iTunes Store or App Store purchase you did not make. The email will contain a link soliciting your Apple ID to confirm the alleged purchase. Both the link and the receipt are fraudulent.
Read Avoid phishing emails, fake 'virus' alerts, phony support calls, and other scams - Apple Support.
The proper action is to delete the email in the usual manner.
... when I try to cancel the order it sends me apple.com and I try entering my apple id it says it's been locked
In so doing you already divulged your Apple ID credentials to criminals. Most likely, it has already been sold. Subsequent requests for additional personal information like your social security number just adds insult to injury. Recover from that event by following these instructions: If you think your Apple ID has been compromised - Apple Support. The applicable section contains instructions to reset your password as soon as possible and review your account information.