Please go here and be sure that the posts in question were actually published and are not in your draft posts > Dashboard > Posts > Draft Posts
I have viewed your blog and to me that you do not have a clear understanding of three very important things.
1. Posts and pages are completely different. Please see here > http://en.support.wordpress.com/post-vs-page/
2. The method used to sort posts, not pages, is to assign categories to your posts. Please see here > http://en.support.wordpress.com/posts/post-categories/
3. Some themes have a feature called "custom menus" and the theme you use Twenty Ten is one of them. The themes with this deature allow us to place categories in the horizontal menu (black bar on your blog) where the tabs for static pages are normally displayed.
Have you ever wanted to have a different title for one of your pages than the label displayed in your site’s navigation?
Ever wanted to change the order of the list of pages to an order you chose yourself?
Ever wanted to be able to mix pages, categories, and random links in your navigation instead of your theme deciding for you?
If you answered yes to any of these questions, you’re in luck! The new custom menus feature will do all those things.
To create a custom menu for your blog so you can display categories in the horizontal navigation bar (black bar on your blog) please follow these instructions. > http://en.support.wordpress.com/menus/
If those instructions are not sufficient for your needs then perhaps Custom menus arrive at wordpress.com will be helpful.
Hope this helps.