“Write A Post” Box Too Big – Spreads Under Boxes on Right

Greetings,
I’ve been using the Write a Post box (under the tab “Write”) for months and it’s been fine. But now when I hit “write a post” the empty box first pops up for a second at the right size, then expands a .75″ to the right going under the Password Protect, Dicussion, Categories, etc., boxes that line the right side of the page. I can’t see the text under the boxes but can see the text in the gaps between the boxes. The Title Box stays at the proper size.
Weird part – my partner’s Write A Post page is fine hwen he logs into our admin/manage section. he did just change our template on the website itself and the timing is more than coincidental despite the fact no changes were made to the “write” pages.