Admin unable to post on my own blog

I suddenly have a really strange problem with my blog. Admin (me) is no longer an option as author for posts on my own blog. I recently added a new plugin (FeedWordPress), so my first thought was that it caused some issue. I deactivated the plugin. I deleted the plugin. I still couldn’t post as myself or edit a post to say I made it. I logged out and back in again. Same problem. I changed my password, logged out and logged back in. It’s still the same. Does anyone have any idea what is happening here and how to fix it? I really need to get this back to normal. I made another account so that I can post, but I want my original admin account working properly.
Thank you.