kellyman - 11:05 pm on Mar 22, 2012 (gmt 0)
In this last week many sites have suffered as you, I really dont think its the links you just had created but rather what had happened in the past.
I would put it that Google has devalued a hell of a lot of blog networks, so if you did happen to have a link on one of those pages I would say the value has gone.
As someone mentioned above try and get some quality links to your site, im sure you will recover in time.
The exact same thing just happened to me and it was my first thought i had been penalized, but im sure if that were the case you would be a lot further down than position 7
Funny enough my main keyword also dropped to position 7 which had been rock solid for over a year.