I think ‘off’ might be more that she was pissed off, as opposed to upset, as she was allocated a baby in room 3 but wanted to get into room 1.She said she was ‘off’ after Baby C and her colleague said she couldn’t say anything to help her so she must have been upset at work then too.
“or was it just Lucy cause she was present or had other sinister feelings of guilt”
Her text don’t seem to express any guilt to me. She’s not asking ‘did I do anything wrong’, but is giving ‘reasons’ why the babies died.