I Have Been Experiencing Stomach Pains For The Last 4-5

I have been experiencing stomach pains for the last 4-5 days and have not been able to eat. i have vomitted a few times but no signs of anything unusual. i went to the doctors and they said it is cramps but that would not last this long and make me lose appertite and vomit. ( researched online). i get this feeling quite often and have had it 3 or 4 times the last few months each time lasting 3 or 4 days. any idea what it is?