security alert email. What should I do?

I received this email from what seems like the correct apple address.

Dear Kapil,

Your Apple ID, <correct apple id was entered here>, was just used to download 谁是狼人-一场谎言与推理的对抗 from the App Store on a computer or device that has not previously been used. You may also be receiving this email if you reset your password since your last purchase.

This download was initiated from China mainland.

If you initiated this download, you can disregard this email. It was only sent to alert you in case you did not initiate the download yourself.

If you did not initiate this download, we recommend that you go to iforgot.apple.com to change your password, then see Apple ID: Security and your Apple ID for further assistance.

Regards,

Apple

How should I handle this? I have already changed the password and challenge questions on my apple account. Do I need to do anything else? Should I be concerned about security of other accounts?

Please advise

thanks

Kapil Sood