You can use the Creative cloud Desktop to uninstall/reinstall. Sometimes you may be asked to sign in, but since you signed up and paid for your account, you should be good to go. Also not I have both Photoshop CC and CC 2014. You can install both free of charge and then you have two working copies of Photoshop.
So to uninstall, click on the gear that you see next to CC 2014. When it is done uninstalling, there should be an "Install" button.
