I solved this by adding following rewrite rule just above the if statements for the geoip redirection

if ($request_uri ~* ^/admin)
{
break;
}

That solved the issue, now when someone from germany goes to site root they will still be redirected but if they go to admin section of the site, it wont redirect, thanks a lot Rainer and Maxim.

http://www.somerorbay.com