It is IMPOSSIBLE to miss type 1 diabetes.
If the two tests came back normal, then your symptoms are not being caused by high sugar levels.
When someone is actually developing either form of diabetes, their blood sugar levels DO NOT return to normal levels. Also, the finger prick test was most likely an A1C test which measure a THREE MONTH average. When that comes back normal, it means your sugar levels have not been high enough to be out of normal range during the last three months. No matter what you eat or drink or don't eat or drink before an A1C test, it can't be fooled.
You may have a virus. You may have low blood iron. You may even have an issue with your thyroids. Any of those things can also cause you to feel tired and lethargic.
As for eating more and going to the bathroom more, that might just be coincidence and not related to whatever is making you feel bad. Depending on your age, you may be about to hit a growth spurt and your body could have triggered the extra hunger to prepare for the growth spurt. You didn't mention your age - but you did mention your mom, so I am guessing you are under 18.