You got what you purchased, yes......Bacopa monierei.
But you obviously expected something else........ Micranthemum umbrosum.
Bacopa monierei is somewhat "stiff" in appearance and a touch of faded green, exactly like your pic. Leaves elongated eggshaped. It will likely grow a bit more compact, as it adapt to life under water. It is one of the easiest stem-plants to grow.
Micranthemum umbrosum will appear "delicate", as you describe it, stems softer and often arching. Colour usually a brighter green. Leaves more round. It has requirements, that takes some skills to fullfill, according to light, ferts and aded CO2.
P.S. I would trim the stems soon and replant off-cuts inbetween, to promote branching and a more dense group of plants.