Hi! Do you mean you can't find the image on Pinterest?
When you created the pin you would have had to choose a board to save it to but sometimes it's easy to accidentally pick the wrong board. I've done this myself a few times! I would look through your other boards to see if it ended up on one of them. You can find them all in one place if you click your profile image in the upper corner of Pinterest.
Once you have located it, you can look at this post on how to embed from Pinterest or if you have access to the Orientation forum, this post that has some additional images.