Yes. If you eat a lot of sweets, little protein and go long periods between eating, it is most likely hypoglycemia. Shakiness and altered mood are classic symptoms of hypoglycemia. Eating protein only for breakfast, eliminating sweets and artificial sweeteners and eating small protein snacks every 2 hours can eliminate the hypoglycemia symptoms. Hypoglycemia can be misdiagnosed as bipolar & adhd.
No such thing! The symptoms are from a fall in glucose, not from low glucose. If you sugar dropped from four times normal to only three times normal, you would have the same symptoms, even though your sugar was still 3 times normal. The symptoms go away just as fast if you don't treat them. Treating them can actually cause them to recur over and over again. You are probably obese and Insulin resistant.
Test it. Test it. Next time you are moody and shaky, drink a glass of apple or orange juice. If it fixes your symptoms right away yes - these were symptoms of hypoglycemia. If you stay grumpy and shaky after the sugary drinks - something else is going on.