AVG Internet Security 2015

Huihui, For basic upgrading info have a look @ this article (http://avgclick.me/UpgradeToLatest).
AVG Guru

Hi, 

I had just reactivate my existing Internet security 2013 with a new registration key (for Ineternet Security 2015). This was done without uninstalling the 2013 version and I did not run the CD for 2015 version for installation.

Can I check do I need to uninstall the 2013 and re-install with the new version? 
If i do this, will I be able to reuse the license key? 

Appreciate any help given. Thanks.

Huihui, For basic upgrading info have a look @ this article (http://avgclick.me/UpgradeToLatest).
AVG Guru