If people had manually modified your posts, there would be a 'last edited by' line at the bottom. If you don't see that, then it hasn't been manually modified by any Admins/Mods, or even yourself.
Now, could a mod have added a word filter that affects the whole forum whenever somebody posts a word? Yes. That wouldn't cause the forum to get tagged with the 'last edited by' line. However, we will not confirm or deny what words may be on that list.