I have deleted my own threads before but it was like within minutes of posting and no one had replied. I clicked edit and it asked if I wanted to delete.

This is from the FAQ

Can I edit or delete my posts?

If you have registered and are logged in, you can edit your posts for up to 4 hours after you've posted it.

To edit your posts, click the Edit Edit / Delete Message button by the particular post. If your post was the first in the thread, then deleting it may remove the entire thread.

Once you've made your modifications, a note may appear to inform other users that you have edited your post.

If the edit time and date appear as a link you can click on this to see the differences between the original and edited versions, or between edits if there have been multiple edits.

You cannot delete your own posts. Report a post if you need it deleted, and a moderator will take care of the deletion request.

Can you delete all of my posts?

No, we do not have that option. We do not do wholesale deletion of a member's posts. If, however, you have a few posts you need deleted for safety or personal reasons, we can do that