With out logging in it would be hard to access but this one is your blog home page : http://www.fateyes.com/blog/ , so should be listed under 1 of four sections in your admin panel, post,page,all in one seo settings or theme settings.

You Should have the option when editing the page content, you may have close the tab which is below the content box, should say (ALL in One SEO Pack), so click to open it.

Actually i have seen sites thrive with the same description, How ever think of it like this when you search for a product for example say a kettle most results have the word kettle in the description and it is highlighted by Google in the search result so relevant, so if yours is the same through out the site that is not going to happen and the chances are the user will click one that has got the keyword in.

Yes you can change them any time, when the page gets crawled again the description will be updated  in search results, try to avoid duplicates & I also recommend  putting your keywords in the page meta but at the same time maintaining good quality description for the end user.

If you want to find all your indexed pages in Google just type:  site:yourdomain.com or .co.uk or other  without the www.