you've got the power
You can edit your posts by either clicking on the pencil icon next to your posts (Be sure to save your changes using the "Update" button in the editor) or by using the dashboard (click on comments, find your post, hover your cursor over the post and you'll get options for editing, or trashing, etc.)
Depending on how it was initially posted, you might not be able to edit the title of your comments. If so, copy your body text to the clipboard, trash the comment, and repost.
Honor code applies, natch.