Hi, and welcome to PZI!
I did see your post in the Health forum, but glad you came on over here. This is a fairly small group, but very active and always pleased to greet a new member.
You did nothing wrong, is what I'm thinking. If you got two readings that close together, it sounds like the meter is accurate. To be sure, you can poke your finger and test your blood. I've done it and so have most people (let us know what reading you get).
Question- what was Ozzie's last test before that one? Was it the 345 at the vet? I'm trying to get a feel for why the vet bumped him up to 3 units, from 2 which is already higher than "normal" for newly diagnosed sugarcats. Most vets recommend 1u twice a day (BID in our lingo). On diagnosis day, do you know what his BG number was?
Not shooting at 69 was 100% the right choice. 3 units into a number that low could have been disastrous.
Oz will become less traumatized as each day goes by. The key is post-poke treats. Always have a supply of low-carb treats on hand. Kitties get one every time you stick them with a lancet or a needle. Eventually they learn that pokes mean treats, and they associate the routine with the added bennie of feeling better. Just about every cat reacts that way to testing at first. And just about every cat ends up coming to you to remind you it's test (treat) time within a week or two. Bob hears the test case zipper, and he's purring, rubbing my legs, and laying down at my feet waiting for his shrimp. The test is a minor inconvenience if the reward is a fresh shrimp!
Tomorrow morning when you test him before his shot, if possible, post the number here before shooting. What time would that be? Maybe one of us can schedule themselves to check in around that time. In general, we would tell you to not shoot on any number less than 200. Most likely, the group consensus will be that you should start with a dose of 1 unit. That establishes a baseline for what the insulin does for Oz. Would you be able to test him 5 or 6 hours after that? PZI reaches peak effectiveness usually 5-6 hours after the shot. At that time, Ozzie's BG would be at the low point in his cycle. Knowing that number is the key to how a dose works. A combination of his pre-shot numbers and his nadir number is used to determine what sort of dose will work best at this point in his treatment. As time goes by, that dose might increase or decrease, but it usually takes a few days on the same dose for him to "settle in" to the dose, and then you can determine which direction the dosage needs to go.
OK, so again, welcome to our little group. I am sure some of the others (some of whom have already replied in Health) will chime in soon.
Carl and Bob in SC