Baby ate her poop

I took off baby’s diaper so I can give her a bath. I leave her for two minutes to get her face towel and comb, I walk in on her sitting on a large poop, smashed all over the floor, her face and mouth then two fingers inside her mouth. I open her mouth and there is a lot of poop inside her mouth. She is looking at me like.... where have you been?

I rush her into the bath immediately and wash as much as I can. Use a towel to get the poop from inside her mouth but certainly she has swallowed some. I give her lots of water too.

It’s been two days now and she hasn’t stopped pooping. Like about 6 times a day and very watery and green. I started her out on ORS to rehydrate her. At what point do I take her to ER???