Blue US passport in black leather sleeve

I lost my blue US passport yesterday around 3pm near Union Station in downtown Worcester. It's a standard U.S. passport book inside a black leather sleeve with a tiny red heart sticker on the sleeve. The passport was tucked in the zipped inner pocket of my gray North Face backpack; I recall walking past the Worcester Public Library on Salem Square and then toward the DCU Center. The sleeve has a small crease on the bottom edge, and the passport feels fine, but I'm really anxious because this trip was important and the passport is essential. If anyone finds it, please email me at [email protected].