Hpts come out negative, but i can hear a heartbeat in the womb. how is this possible?

Likely your own beat: If you hear a rhythmic beating sound over your lower belly, try to see if it always beats at the same rate as your own heart.A "bruit" or blood flow noise can be heard over narrowed arteries of the kidneys or other pelvic organs in some.It will always match the pattern of your own heartbeat.A fetal heart beat, if audible, will have a separate pattern & generally run much higher than yours.