My knees are higher than my pelvis with the fit ball too, but I'm trying to encourage baby's head into my pelvis as much as possible so I'm constantly moving, its quite comfy now I've gotten used to it and good for lower back pain (or preventing it as I dont seem to have a problem with my back).

I think the mw was saying your baby is a bit too posterior, her back is more to the back of you than your front. Can you feel baby's bum on the front left side of your belly? If so then your right!

All the best,

Beck