I am feeling very weak, nauseous but no vomiting, severe to moderate headache, hungry but no appetite. what may i b experiencing ?

See MD if Sx Persist: 21 y/o female, Feeling very weak, nauseous w/o vomiting, severe to moderate headache, hungry but no appetite asks, What may I be experiencing? Could be a number of indispositions from Simple Viral Gastroenteritis, Food Poisoning or PMS to more complex Liver/ gall Bladder inflammations. With no fever the symptoms may clear in a day or two. If symptoms persist best to see MD for Evaluation & Treatme