Very possible that one of the beats you’re hearing is coming from the cord. Very common & not a problem. Last time my midwife couldn’t get the baby’s heartbeat, so she took the measurment from the cord. It’s the same as the baby’s, of course.

Babies move all over the place, and just the baby flipping over can cause the heartbeat to be found somewhere else. And even though it may not sound like your own heartbeat it can be, I had none stress test 3 times a week when I was pregnant with my 3rd, and a lot of times they would find what they thought was the babies, and it was mine.

could be twins U/S arent always right sometimes ones behind the other and you cant see them or your baby is transverse now and ur hearing the heartbeat b/c its stronger now.

As the baby grows, the heart gets stronger, so you can hear it from further away.

sometime it can pick up your heartbeat,or it could be twins