Can’t Make New Posts

Recently I had updated a blog to 2.5 from 2.3. Everything seemed to work fine, until I tried to make a new post. After typing up a post and clicking save or publish, it would say post saved (or post published), which is normal. However when I went to view my blog, the post wasn’t there. If I go to manage to view posts/pages in WordPress admin panel, the new post also doesn’t appear there. I know it tried to do something because I am using a Twitter plug-in that notifies my twitter page that a new post was made on my blog. The mention of the new post appears on my twitter page and provides a link to it. Of course when I click the link, I get a page not found error.