Being addicted to sweets is connected to type 2 diabetes. People used to think that eating all that sugar over a long term is what caused diabetes, but these days the thought is that a 'sweet tooth' is genetically related to the likelihood of developing diabetes, that they are both the same gene.
I was told I was 'pre-diabetic' about 10 years before actually becoming diabetic. At that point I wish my doctor had told me some things. Which I will now tell you for free. 8^)
Most diabetics are not aware they're diabetics because the symptoms of the disease are very subtle at first. (Being tired after a large meal is NOT a classic symptom, but the actual symptoms are different for everyone.) When new diabetics finally get their blood sugar tested it's grotesquely above healthy levels and they have already suffered some damage (which we call 'complications') like kidney failure, losing vision, heart disease, etc. So at the very least you should get your blood sugar tested every 6 months or a year (at the most) for the rest of your life!
It would be helpful for you to begin living like a diabetic, working to control your blood sugar. This means diet and exercise.
Diet means moderating carbohydrate intake--cutting out things like bread, pasta, potatoes, rice, etc. And really back off on the sweets. You can have a -taste- of dessert after dinner. A bite or two small bites of chocolate as you start your exercise period. This is not one of those diets where you lose 15 pounds in a month and then go back to your old habits. Make changes slowly and carefully, changes that you can maintain indefinitely.
Exercise doesn't mean huffing and puffing at the gym. I started with 3 45-min. walks a week and graduated to ten miles on the bicycle. Walking or biking while listening to audio books or podcasts on my phone.
You might consider getting a glucometer. That's a gizmo that measures your blood sugar. You test your blood when you first get up ('fasting') or 2-3 hrs after a big meal ('post-prandial'). The instructions will tell you the normal ranges, or you could look them up on the Internet. Walmart has a very cheap model (brand name: Relion), something like $20, and the test strips are like 20 cents apiece. You also use the glucometer to see how different foods affect you--for instance, I can half half a potato and it won't show but the equivalent amount of rice will spike my blood sugar. We're all different.