Yes, I think Jennifer makes a lot of sense, and has been what I suspect a little too. I do think the role of the staff (and of people, by nature) is to sugar-coat or slightly enhancing the truth to prevent you from worrying.
My frustrations often surrounded the feeling that very few expected me to have researched and read about this stage in mum's illness, and that to protect me, they kept the details from me. I like to think it's out of kindness, however frustrating it was at the time. I knew what to expect and I really needed to know if we were at each stage, especially as I thought we were and desperately needed confirmation. However, when the staff have it all in hand, which I'm sure they have, they keep family at arms' length so when we leave our loved one, we're not constantly worrying about how much food or fluid they've taken. But that doesn't stop us, and that's the problem.
Like me, you really want the truth, because it's not adding up. I used to wonder how they achieved these claims that mum took so much more fluid for them than for me... After all, I didn't have other residents to look after. I had all the time and patience in the world, yet mum physically couldn't take more than I was giving her. I always suspected it was either forced, spilled or exaggerated. The latter is the more likely scenario. They have such responsibility, and to put your mind at rest, I definitely don't think it's to show who's better at the job... I really don't. I just think they are following orders and certainly attempting these amounts, but are maybe worried they'd be in trouble if they didn't give her the "required" amount (though we all seem to agree that's too much, if she's refusing it...but that's another story).
There's no way of ever knowing for sure, but you do have a trusting bond with M, the night nurse, so I would simply take that fact as your sleeping aid tonight, and know your mum's in good hands. I hope, from the bottom of my heart, that you and your mum both have a good nights sleep.
Build up some strength for tomorrow and see it as another day. That anxious knot will pass, because you will be hearing from the GP this week and know for sure you're not letting your mum down. We all know that, and now we just need you to know that too.
Sweet dreams, and sleep tight, xxx