You could very likely have a pollinated plant, likely self pollinated (hermie). As mentioned above, you can remove a piece to see if a seed is forming.
By the way, what you're calling a calyx is actually called a bract. The calyx requires a microscope to see and is nothing more than a thin layer of skin INSIDE the bract. A misquote in a 1980s High Times issue is to blame for this incorrect nomenclature.