Jetpack and WordPress account issue when self hosting

Hi, I have downloaded WordPress and created a Username/Password via the Package Centre of my Synology Diskstation.

I am having problems getting Jetpack to connect to WordPress and, after reading round lots of forum posts, I think I have found the issue but I don’t know how to resolve it.

I read this:
Jetpack requires a connection to WordPress.com to enable all features. This is a different account than the one you use to log into your self-hosted WordPress. If you can log into http://wordpress.com, then you already have a WordPress.com account. If you can’t, then you can easily create one as part of the installation of Jetpack.

So I tried logging into WordPress with the username/password I created and discovered I can’t. If I try to register my account, I am told the username is taken, (could be me but I suspect someone has already taken it, as I couldn’t use it to sign up to the forums).

I know my site is working, because I can access it, so I must have created it correctly.

So how do I get my WordPress account registered so that I can install Jetpack??

http://wordpress.org/plugins/jetpack/