Help Needed With Editing Center Column

I'm sorry if this has been answered before but I've been searching for the past hour and can't seem to find a thread that can help me.

Anyway, I've been trying to edit the center column without much success. I am trying to add a box with some text in it to appear only on single posts after the footer area.

I added the html after the code below in the 'Content BELOW the LOOP' section of the 'Style & edit CENTER COLUMN' section:

<?php /* Displayed on SINGLE post pages if activated at ATO -> Next/Previous Navigation: */
bfa_next_previous_post_links('Bottom'); ?>

[I added the html code here]

However, the box appears on my 'Pages' pages also.

How do I do it so that it only appears on the 'Single Posts' pages only. (I am using version 3.4.1, WP 2.8.1).

Thanks!