Posts over “show at most option” mess up side blog…

Here is my blog: https://atlantahatesus.com
Here is a screenshot of it jacked: https://atlantahatesus.com/ahu_jacked.tiff

Its hard to explain but in the admin panel, under reading options, i have to keep upping or lowering the “show at most” because I had it set to 15 and the other day and it jacked the sideblog….

Example…right now it is set to show 20 posts. If I make a test post it is fine, if I make two test posts it’s fine, when I make the third test post its screws up. So then I can lower the “show at most” to 15 and it looks normal again….

Any ideas? It’s not a huge deal because I can mess with it after posting to look ok, but it is just a little pain.

Thanks!