Just how bad is it to sleep on your tummy at 8 months pregnant?

I've always slept on my tummy and lately I've started to roll onto my stomach in my sleep. I don't know how long I stay that way but I always wake up in a lot of pain and I'm worried I'm squashing my baby. I haven't felt her move much today and normally she's really wriggly

I'm seeing my obstetrician tomorrow but I can't help but be nervous.

I've set up barriers for myself in bed but I must move them in my sleep because I find all the pillows on the floor

Am I doing a lot of damage to her?