I am not sure if this is an eating disorder issue, or lack of appetite due to stress or depression or other issues. It would be a doctors decision, and i agree you should consult one.
In the meantime, dehydration is more dangerous and will make you feel worse faster, so be sure to drink lots of water, sports drinks, vegetable juice, milk, soy milk, etc. If you are willing to have the calories, a great source is peanut, or other nut butters. And the protein shakes are a great idea. You can also get the powders you can stir into water from places like gnc.
Please take care. Hope you feel better soon.