Celeste,
I just read your other post and this one.
So, let's start with some questions for you to answer - ok:
1) what size (gauge) needles are you using to give the insulin?
My guess is you are using anything from a 26-28 gauge. If you are, then I recommend that you get different needles - ones that are 30 or 31 gauge - and get the short needles.
What does this mean - the lower the number the larger the needle. The reason Jimmy may be feeling the shot - is because you may be using very large needles. Depending on the state you are in, you may need a prescription for the syringes - if you have a walmart nearby - you can pick up a box of 100 syringes for about $13.
So, what you need to tell the pharmacist and/or have the script written as is the following:
U100 0.3cc 31 gauge 5/16" length (short needle)
When you get this, compare it to what you have and you'll see a huge difference in needle size.
2) are you familiar with home testing yet? Are you willing to learn how to home test Jimmy?
Again, go to Walmart and pick up the relion brand glucometer and matching strips - make sure you get the one that only requires a small amount of blood and the strips are "sipping" strips.
Once you learn how to home test, you will be in control and able to test Jimmy to find out if the amount of insulin you are giving is too much.
3) others mentioned food - I'll reiterate here: you don't need to feed the prescription food - it's expensive and not any better quality than what you can get in the pet store. You can return the opened bag and cans to the vet for a refund. It's guaranteed. So you're not out money.
then to start, either buy fancy feast - classic flavors, or friskies - pate flavors
Additionally, pick up a few cans that are gravy based and keep them apart from the daily foods. You may need them in an emergency situation.
If you tell us where you are located, there may be someone close by who can provide in person assistance.