It certainly looks like you have some adult fish in the pond. As you probably noticed when you stocked the quarter size Bluegill, they look like miniature adults. The small fish you saw were apparently easy to catch in a bucket and even at dime size should also look like a miniature adult. Catch some more and take a close look. If they happen to be Bass, they will not look at all like Bluegill, but very much like small Bass. They often have a fairly prominent lateral line even when quite young. Good luck with the search.
Jim