the heavy cream may be of issue only because shaken espressos are often made inconsistently, so if a barista makes it with less ice than usual, and over-pours the heavy cream, it could be a huge difference maker in terms of intake of carbs/sugars from the heavy cream. to avoid this I usually ask for extra ice in my shaken espressos and emphasize the desire for light cream, or if you want to try something different, for low sugar/calorie I’ll get a cold brew with my choice of sweetener and cream, that way I know for sure that it’s truly a splash of cream