Ok you did great last night! And made the right decision no insulin this morning.
Now that the crisis is passed, let's go over some basics so you can better understand all this.
1) Food/nutrition - Now, as far as diet - definitely dump the dry food (if you are feeding any) and if the vet recommends purchasing prescription food like DM just say "no thank you". ALL cats, and especially those with diabetes, do best on a species appropriate diet that is high in protein and low in carbs. Dry food DOES NOT fit that bill and DM food, even canned, just really isn't that great as far as quality. Most here on FDMB feed low carb/high protein canned, raw bought from a pet store or they make there own.
Here is a link to a site by a vet "Dr. Lisa DVM" ... who also posts on this board from time to time ...
www.catinfo.org
If you look on the right side of her site, she has a food comparison chart to help you figure out what food you want to get based on the carb %.
You want to keep the carb % below 10% and around 7% is great. (Personally, I stay between 0-6% carbs.)
While on her site, you can read about in-depth info. on nutrition and how to make raw food, etc.
Here is another link that will give more information about food/nutrition
Nutrition/food info
The good thing with feeding your diabetic cat this way, is that it is ALSO good for any non-diabetic cat too. All your cats can safely eat the same food without worry and it may save you some costs and headaches of having to do separate feedings and keeping track of what they are eating.
The meow mix with gravy is a high carb food and was perfect for last night. You don't want to feed this as her every day food because it is too high in carbs and you will have to adjust the insulin too much because of the food. I suggest if you still have this food, to keep it - label it high carb and separate it from the low carb food you will use. If you have another incident like last night, you can break it out and use it.
2) Home Testing - Thanks to Jamie - you are now a pro at home testing and it's self explanatory why home testing is critical in monitoring diabetes and BG levels. So kudos to you on this.
3) Insulin - you are using Lantus and that's great - Lantus is an excellent insulin for cats. My only concern is that you are at a higher starting dose than we would like to see.
Could you tell us a few things:
When was your cat diagnosed?
What was the starting insulin dose?
How did you get at 3 / 4 units of insulin?
We normally recommend a starting dose of 1 unit or even 1/2 (0.50) units twice a day. This the the start low, go slow approach. The reason we recommend starting out this way, is to avoid the hypo incident you had last night. By giving a higher dose 3 or units at a time, you may have skipped over the ideal dose which could be 1.5, 1.0 or even 1/2 unit.
As you become familiar with this board, you will see we have several forums here. The health forum (where you are now) is a great place to get started. Once you get comfortable, create a spreadsheet to track the BG's, insulin doses etc, we suggest posting on the Lantus Tight Regulation Forum. There are lots of folks there who can help tweak the lantus dose. We can do it here, but there is always someone on that forum.
That leads me to next steps and now what. Keep testing and if she is 150 or below, at this time, I would suggest NOT giving insulin. Seeing that she was 107 this morning with all the high carb, gravy and syrup given, that is fantastic to see.
It can also mean that if you change her food to 100% low carb wet only, the need for insulin may no longer be necessary. It is possible to control her diabetes with food. Now that doesn't mean you stop testing and monitoring her. It just means she may not need insulin, or may only need a very small amount.
If you do need to give insulin, I also suggest starting over and following the start low, go slow approach and restart her by giving 1/2 unit at a time. This will help to keep her safe and hopefully avoid another incident.
Ok - here are links for you:
How to Get a SS and Link in your Signature --
viewtopic.php?f=6&t=18207
Help with signatures/links/images/avatars here! --
viewtopic.php?f=6&t=486
Board index » INSULIN SUPPORT GROUPS (ISG) » LANTUS (GLARGINE) - Tight Regulation -
viewforum.php?f=9
In this forum there are several posts that are starred/called stickies that I suggest you read - it will give you details about Lantus, how to use it, etc. that will be invaluable
Dr. Lisa's website -
www.catinfo.org
Gives you the food chart comparison list, explains why dry food is bad for cats, and a host of other valuable information about vaccinations, UTI's, etc.
Please come back and ask questions - we are here to help and will do everything we can to help you and Baby!
and yes, get some sleep 
