Hello there, I can understand your concern. Its good to know that you have made an effort and succeeded at losing weight. It would have helped to know your current fasting and post meal blood sugars. The symptoms you have described could be due to low sugars but since you are not on any antidiabetic medicines it seems unlikely. The other thing to rule out is thyroid related problem. Please visit a physician who can examine you thoroughly and get some blood tests like CBC, and thyroid function tests to find the cause for insomnia and tremors. Hyperactive thyroid can some times produce these symptoms. Till then continue your low carbs and exercise pattern. Take care.