I started feeling mine are 20 weeks and he can see her clearly now at 25 weeks. She's so strong, my belly takes on a whole new shape when she moves. I'm a size 16/18.
Firmer* not for me...sorry.
My SO felt the heart beat and the some movement that I felt on the inside. Just let him rest his hand a little for me on your belly. And my little bean is has been a mover and a shaker since 10 weeks but it also my 3rd so I know what to look for also far movement.
It took until I was 27 weeks to actually see my baby moving.I felt him moving at 23 weeks though Lol you could actually see skin moving when baby moves.