I'm a beginner in SEO and I was wondering if my blog has been penalized by Google. Actually, my blog have many duplicate content issues such as copied content, duplicate meta tags, duplicate title tags etc. I've submitted 162 web pages in the Google Webmaster's tools and it shows that it has index all of my pages but when I do site:url.com it only shows 110 pages in the SERPs while the total pages indexed are 162. I've also tried the other ways to check if Google has indexed my new pages or not, but it won't come up in the SERPs while in Webmaster's tools it shows that the new pages are also indexed. My home page is not removed from Google SERPs and also the 110 other pages are not removed. The only problem is with the new pages and posts because they won't show up in SERPs. Is my blog penalized ? If not, what could be causing the problems and what are the solutions ?
Addition Detail: I've messed up with Google Fetch option in the webmasters tools and I think that's why the <title> tags of my blog are not correctly indexed. e.g showing the title "Newer Post - My Blog Name" in the SERPs