there could be a number of things that could cause you to have problems falling asleep and this doesn't necessarily have to be related to your problems with hunger and stomach cramps. It would help to know how old are you, are you male or female or if you had any problems with your weight and appetite before this started to happen. Also, you say you're hungry all day - do you always end up eating something or are you managing to control your hunger? Do you have the cramps every morning?
One thing you can do is to try and see if it's food related allergy by cutting out dairy and gluten from your diet for a few days, to see if cramping is caused by lactose or gluten intolerance.
Wish you all the best,