Wow! The symptoms that you are describing sound exactly like a hypoglycaemic episode. Feeling faint, agitated, palpitations, HUNGRY, restless? Having these symtoms does not mean a person is a diabetic, but it does show that his or her blood sugars are not within a normal 'safe' range at that time. Anyone who eats too much sugar will get these symptoms.
Hypoglycaemia occurs whenever a person eats a large amount of sugar - the sugar creates a flood of 'energy' to the brain, which makes he or her feel full, excited, happy. Within an hour, the body mounts an insulin response to clear the sugar out of the blood (too much sugar in the blood is dangerous which leads to diabetics complications). When this occurs, often too much blood sugar is cleared - and too quickly - hence the symptoms that you have so aptly described. The sugar has plummeted from very high to dangerously low.
The cure is to eat less sugar, in your case - less fruit.
What is a lot of fruit? I think that one or at most two pieces of fruit a day is safe, but more than that means you may be getting too much fructose (the same sugar that is in soda pop), which is unhealthy for the liver. Eating this way may also lead to diabetes in the long run.
Your body is telling you that you are eating too much by these symptoms. Once you cut down on your fruit intake, you will find that you will be much less hungry. I would even suggest that if you do eat fruit, make sure you have some protein (cheese for example) with it, or some healthy fat.
And remember it is best to eat fruit with the skin - not peeled or juiced.
Hope this helps
Dr Vera Tarman