"But the 2 hour sit down she's getting is driving me nuts! I sat down for a sum total of 7 minutes yesterday, one of my days at home."
You seem to have accepted that the posters here are right about what tasks you can ask a nanny to do - which is fine
But there is something else. You have to disconnect from being "driven nuts" about her getting a sit down (if there is still time for one when she has done all the reasonable child-related things).
She isn't you. It's your house and your family. She's a paid employee.
If you were the receptionist for the CEO who owned the company, would you think it reasonable that he expected you to stay all night when he stayed all night? Just because he has to, so why don't you?
Respect her. Be nice. Draw up a reasonable list of additional things: child laundry, child food, etc, and suggest that she get to that when she has time. Say that you didn't expect her to have any time when the baby was up and down all the time, but you hope things have settled down a bit now, and she should probably have time to get to some of this. Don't check up on her. Trust her to be reasonable about a balance between working flat out and being strung out, and lounging about on her phone.
If it turns out she is actually a proper piss-taker, get a new nanny. If she doesn't work at the flat out pace of a mum in her own house at home with preschoolers, cut her some slack - it;s not her house.