After changing the email address to my appleid I still receive emails about purchases on the old email (as well as the new).

I recently changed the email address that was my Appleid. I verified it and followed all the steps the web told me to do. I signed out of itunes on my laptop and back in. I signed out of everything and back in on my ipod touch.

Today I made my first purchase since that change, it was on a new computer. I authorized that computer and went through the steps itunes asked me for, password, security questions and so forth. I received an email stating a purchase had been made on a new computer.

The problem is that I also received the same email at my old email address as well as the new one.

When I check my appleid on the internet it says that only the new email is associated with the appleid. Which is how I want it. Why did the old email address get the mail as well as the new? Is there any way to stop that from happening in the future?