Good news that you are able to be close to her
Write in a notebook all the things that happen to her, great to read later cos otherwise it will be a blur, and your feelings
Also take loads of photos and videos
My premmie is now over 6' tall but we still remember the NNU ITU
It is great that she gripped your finger that shows she knows you are there, talk to her cos she will recognise your voices 
Read her stories or just anything that you have with you even if it is a magazine or newspaper or talk about the rest of the family or talk about the weather just anything so she can hear your voices
There will be lots of strange noises like beeps and machines making loud alarms going off with the other babies so you talking or reading or singing will be noticed by her
Is she intubated or on CPAP?
When she is stronger you will hopefully be able to give her KANGAROO CUDDLES it is a special way to cuddle her skin to skin inside your shirt - even with all her wires and cables the nurses will be able to help
At the moment you need to get some rest and get yourself stronger too, hope you all have a good night 