With DS our OB used the stethoscope from a little later on in the pregnancy, so maybe it won't be too much longer till you can just use that. Baby's movement is probably a better indicator
I agree with Arcadia about feeding anxiety. I understand why you need the extra reassurance, but that may be better gained through close contact with a caring and understanding caergiver, as well as taking time to care for yourself.
I hope you're doing well adn baby is kicking up a storm soon