Links to certain posts not working correctly

My latest post, wiht a category of Weekend Reading, is not behaving. If I click on the post excerpt on my home page, instead of viewing the full post I am taken to a list of excerpts of two posts in the Weekend Reading category. I can view the older post by clicking on Read More, but when I click on the newer post I loop back to the same screen with two post excerpts. I tried deleting and recreating the post, and I even removed the Weekend Reading category - it's not working.