Must be too early I just tried and couldn't hear anything, so I googled and it said from 18wks you can use a normal stethoscope. I might just do that

ETA: Hopefully I will be able to feel Button move more frequently anyway so wont be so anxious. I can feel little movements but they are very light and irregular.
Could just be too early. We have been able to hear bus with a stethescope. My midwive has used a funnel to listen as well, and DH can sometimes hear her heartbeat now if he just lays his ear directly on my belly - provided she is laying in the right position.