Thankyou for everyones support and suggestions/help

I've been managing to get his blood tested before his main meals twice a day (I mightve missed a day because I was really sick). He doesn't love it, but I am getting better at testing him.
After calling/visiting many pharmacies I found one that will at the very least sell me one lantus pen at a time.

They wouldn't use the coupon :/ but at least it breaks the cost up for me. So I have a few questions I hope someone can help me with.
I currently put the pen in my fridge in a cup because I had read and watched the you tube video on drawing the lantus from the pen, seemed to say that this is the best way to preserve the medicine. Is this right?
Some say that the lantus can last quite a while, is the longevity the same with the pens as the vial? The pharmacist has me concerned as she was very clear about how it will only last 28 days, no exceptions. But I have read so much here debating that.
Moeby weighs about 12 pounds, and my vet wants to start him at 2 units 2x a day. I know I read its best to go low and slow. Should I start with 1 unit? Or the 2 units as prescribed?
Also, the vet tech at the clinic started to get a little testy with me about how I was going to use the pens and draw the meds out. She got on my case about "if I was going to be adjusting his dosage myself, and why wouldn't I just use the pen like its intended." I explained to her that I can get it out with the needles and then I can adjust it more finely if I need to, but I wouldn't necessarily adjust it myself (because I panicked when she confronted me). I mentioned researching online and this website and well lets just say she was not very good at concealing her emotions. Then the receptionist gave me some advice on blood testing on his back foot, but added that "sometimes people do a little too much reading online" :/ Sooo while I am trying to keep my vet in the loop, they seem to disagree with what I am telling them. Its frustrating. They want me to bring him in to go over how to administer the shots, and test his blood again. Also show me how to use my tester, even though I told them I was already home testing. They wanted me to get an alphatrak. I am sure I will get funny looks for getting the relion confirm. Oh well. :/
one last one
I got a box of syringes and they are labeled
3/10 ml cc doses up to 30 units 31 gauge 8mm length
The pharmacist seemed to thing these were acceptable, and I called my vet to make sure. They said U100 but the pharmacy didn't have needles marked as that. So the repectionist checked with the vets and they said they would be fine. My worry is that the needle is too fine of a gauge? Or will these be okay to use with the pen? Or do I have a $13 box paperweight? Lol
This has truly been mentally exhausting to get running.

I would imagine its one of the reasons some people give up early on treating their pets.

I am worried about how exact the time frame for his shots have to be. My work schedule fluctuates a little bit. If its in a one hour window of the same times every day, will that be okay?
Thank-you again for all the help and support again. Its such a relief having found this forum. Knowing there are others out there like me helps so much.
