Hi there and welcome,
I'm sorry about the diagnosis, I still remember how distraught I was when I found out George was diabetic. It took a while to see some better numbers, I followed Tight Regulations (TR) with the help of the folk here on the board, we eventually got George regulated and he went into remission, we had a reasonably smooth ride, others find it harder to regulate their cat. I'm glad you found your way to the board, there's a wealth of experience here just at your fingertips.
In principal what Kathy suggested is good advice, leave food out for him to nibble on while you are out.
Without a little more info it's impossible to give you more Cocoa specific advice. Try not to panic about a seeing a high number, even if it were a bit inflated because you had to poke him a couple of times, I wouldn't worry about that. If I am honest with home testing we don't really see stress induced numbers in the same way you would at a vet's surgery. The testing will get easier, hang in there.
Some important advice (vets don't always tell you)
Always get a BG test just before you shoot, and to ensure that test is not influenced by food, take up all food 2 hours before shot time.
Try to be consistent with shot times, you need to try and shoot 12 hours apart, this works best with Lantus.
Because Lantus dosing is based on how low the dose is taking Cocoa, it's also important to get at least one other test in in every cycle. It doesn't matter where that is anywhere between +1 and +11, whatever is going to fit in with your schedule.
If you are usually away for 9 hours, you might want to arrange your shot times so you are able to get a couple of tests before you leave in the morning, but after you have shot.
It would be really helpful to us, and to you, if you could start using the spread sheet. Most of us track our dosing and BG using these and are very used to seeing data and patterns in this format, allowing us to quickly and easily assess and help you help Cocoa.
Here is a link to the instructions on how to set it up
Spreadsheet Instructions, do shout if you have difficulty with it, we can help you with it if need be.
To help you more effectively, when you get time can you tell us a little more about Cocoa?
What are you feeding him? and when? have you changed foods since diagnosis?
What type of meter are you using? (most of us use human meters, the strips are much more economical and you can save your money for other expenses)
Does he have any other health issues?
How did you find out about the diabetes?