1 unit is my suggestion as well. I just think you need to start it as if she's new to it all. I would do one then test every few hours when you can. Write down the numbers you get and start the spreadsheet. Making a signature would help too. Click on your name at the top and go to signature. Put the insulin type, the cats weight, type of meter you are using, what you are feeding, and any other info you want to share.