When you embed a picture into a post and then see that the post has a missing image, resave the post (select edit, then hit save). 99% of the time this makes nibbles roll over and actually acknowledge your image. This works on comments and primary posts (of course, with comments you have a 15 minute window).
As an aside, I often attempt to resave posts on Oppo (and Photography) that have missing images, and with one exception, it has worked every time I have tried it. (As I have stated before, I do not edit posts otherwise, though I broke that rule once today and created an enlarged image to embed in a post so that I could embiggen it on Oppo proper. Though really all I did was repost the exact same image, just scaled up 20%).
Additionally, when you fall victim to double posts of your original posts (not comments), please take the time to actually delete your duplicate posts by editing them and selecting either "save as private" or "delete post". We do occasionally clean up double posts, but this is more of a housecleaning task and not our primary functions as moderators.