Hi Kitty & Peter. Welcome to FDMB. While you may feel overwhelmed by finding out Peter is diabetic, we can help you learn how to manage his diabetes. Once you find the routine that works best for you and Peter, you will find caring for him is not very difficult.
The important things to help get his glucose levels under control are a low carb canned or raw food diet, a good long acting insulin and home testing.
Most dry food is high in carbs and that is why we recommend a low carb canned or raw food diet. Here is a link to the most recent version of a food chart we recommend. You want to look for foods that are under 10% carbs.
https://catinfo.org/docs/CatFoodProteinFatCarbPhosphorusChart.pdf
We also recommend a long acting insulin since these seem to work better for cats. Good insulins are Lantus, Levemir, ProZinc and BCP PZI. The first two are human insulins and if these are what Peter is on, let us know so we can also give you information that will help you save money when you need to refill his prescription. The other two are designed for pets and can be ordered through your vet or most pet pharmacies online. A good starting dose is 1/2 to 1 unit twice a day. If your insulin or dose is different, please let us know.
Home testing means testing Peter's glucose levels before every shot. You can use either a human glucose meter or pet glucose meter. The human one is usually less expensive to use since the strips are cheaper. Both work well. You test before every shot to verify it is safe to give the dose and help you determine if the dose needs to be adjusted. This is something we can help you learn how to do.
I know you probably have lots of questions. Please ask any questions you may have. The reason this board exists is to help everyone learn how to give the best care for their sugar kitties.