Welcome
@codasajorusa ! Your pond sounds lovely! We'd love to see pictures!
And yes - that COULD be normal. But as
@Mmathis said, every pond is different. How much waater surface, amount of splashing, number and size of plants, heat, and even cold all contribute to water loss from a pond. I will tell you this - almost EVERY new pond owner believes they have a leak. And most of them don't, so you can probably relax.
One thing you can check for is low edges, as those are a common source of water loss. Rocks can settle and push the liner down below the water line both in the pond and on the edge of the waterfall. I've also had plants breach the edge of the pond and push the liner down, allowing for a slow but steady loss of water. Check for damp spots along edges.
Good luck!