My Doppler came yesterday and I've tried twice but I couldn't hear the heart beat but I'm certain I could hear him/her moving around. I'm certain it was the baby coz everything was silent and then there would be a sudden loud whoosing noise - have you heard that too?
yeah i think it's your stomach babe and gas move around
i am 4 weeks further along than you and heard it really low down near my pubic bone to the left as you look down (and it was really feint) i bought mine at about the same time as you and have been trying since then (and sending myself loopy not finding it!!)