Your symptoms point towards a few possibilities-
1.The strongest one being HYPOGLYCEMIA
(low blood sugar
levels) which manifests as excessive sweating
, trembling, palpitation
, and increased heart beat.You might have been maintaining a tight sugar control and developing consequent hypoglycemic attacks(a common event in elderly diabetics) or else there is some change in your meal pattern or physical activity.Just to be sure,please record your blood sugar levels at around 3.00 AM or whenever you have the symptoms. If hypoglycemia is documented you should immediately report to your endocrinologist
and get your treatment revised.
2.The other (remote) possibilities may be some cardiovascular/cerebrovascular/hormonal disturbance for which you should seek advice of concerned specialists.
Warm regards and best wishes
Dr. RAVINDRA MATHUR